From 8ab30c1538b14424015e45063c41d509b24c1dea Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:53 +0100 Subject: KVM: add comments for kvm_debug_exit_arch struct MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Bring into line with the comments for the other structures and their KVM_EXIT_* cases. Also update api.txt to reflect use in kvm_run documentation. Signed-off-by: Alex Bennée Reviewed-by: David Hildenbrand Reviewed-by: Andrew Jones Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier --- Documentation/virtual/kvm/api.txt | 4 +++- include/uapi/linux/kvm.h | 3 +++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index a7926a90156f..9f746eab333d 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -3111,11 +3111,13 @@ data_offset describes where the data is located (KVM_EXIT_IO_OUT) or where kvm expects application code to place the data for the next KVM_RUN invocation (KVM_EXIT_IO_IN). Data format is a packed array. + /* KVM_EXIT_DEBUG */ struct { struct kvm_debug_exit_arch arch; } debug; -Unused. +If the exit_reason is KVM_EXIT_DEBUG, then a vcpu is processing a debug event +for which architecture specific information is returned. /* KVM_EXIT_MMIO */ struct { diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 716ad4ae4d4b..4ab3c6a8d563 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -237,6 +237,7 @@ struct kvm_run { __u32 count; __u64 data_offset; /* relative to kvm_run start */ } io; + /* KVM_EXIT_DEBUG */ struct { struct kvm_debug_exit_arch arch; } debug; @@ -285,6 +286,7 @@ struct kvm_run { __u32 data; __u8 is_write; } dcr; + /* KVM_EXIT_INTERNAL_ERROR */ struct { __u32 suberror; /* Available with KVM_CAP_INTERNAL_ERROR_DATA: */ @@ -295,6 +297,7 @@ struct kvm_run { struct { __u64 gprs[32]; } osi; + /* KVM_EXIT_PAPR_HCALL */ struct { __u64 nr; __u64 ret; -- cgit From 21b6f32f9471284f6d4621fc8be71719266db557 Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:54 +0100 Subject: KVM: arm64: guest debug, define API headers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit defines the API headers for guest debugging. There are two architecture specific debug structures: - kvm_guest_debug_arch, allows us to pass in HW debug registers - kvm_debug_exit_arch, signals exception and possible faulting address The type of debugging being used is controlled by the architecture specific control bits of the kvm_guest_debug->control flags in the ioctl structure. Signed-off-by: Alex Bennée Reviewed-by: David Hildenbrand Reviewed-by: Andrew Jones Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/uapi/asm/kvm.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d26832022127..d82f3f316ba4 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -100,12 +100,39 @@ struct kvm_sregs { struct kvm_fpu { }; +/* + * See v8 ARM ARM D7.3: Debug Registers + * + * The architectural limit is 16 debug registers of each type although + * in practice there are usually less (see ID_AA64DFR0_EL1). + * + * Although the control registers are architecturally defined as 32 + * bits wide we use a 64 bit structure here to keep parity with + * KVM_GET/SET_ONE_REG behaviour which treats all system registers as + * 64 bit values. It also allows for the possibility of the + * architecture expanding the control registers without having to + * change the userspace ABI. + */ +#define KVM_ARM_MAX_DBG_REGS 16 struct kvm_guest_debug_arch { + __u64 dbg_bcr[KVM_ARM_MAX_DBG_REGS]; + __u64 dbg_bvr[KVM_ARM_MAX_DBG_REGS]; + __u64 dbg_wcr[KVM_ARM_MAX_DBG_REGS]; + __u64 dbg_wvr[KVM_ARM_MAX_DBG_REGS]; }; struct kvm_debug_exit_arch { + __u32 hsr; + __u64 far; /* used for watchpoints */ }; +/* + * Architecture specific defines for kvm_guest_debug->control + */ + +#define KVM_GUESTDBG_USE_SW_BP (1 << 16) +#define KVM_GUESTDBG_USE_HW (1 << 17) + struct kvm_sync_regs { }; -- cgit From 0e6f07f29cfb8d79dbbdb12560a73f7121ba324e Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:55 +0100 Subject: KVM: arm: guest debug, add stub KVM_SET_GUEST_DEBUG ioctl MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This commit adds a stub function to support the KVM_SET_GUEST_DEBUG ioctl. Any unsupported flag will return -EINVAL. For now, only KVM_GUESTDBG_ENABLE is supported, although it won't have any effects. Signed-off-by: Alex Bennée . Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- Documentation/virtual/kvm/api.txt | 2 +- arch/arm/kvm/arm.c | 7 ------- arch/arm/kvm/guest.c | 6 ++++++ arch/arm64/kvm/guest.c | 27 +++++++++++++++++++++++++++ 4 files changed, 34 insertions(+), 8 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 9f746eab333d..19adfd385882 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2671,7 +2671,7 @@ handled. 4.87 KVM_SET_GUEST_DEBUG Capability: KVM_CAP_SET_GUEST_DEBUG -Architectures: x86, s390, ppc +Architectures: x86, s390, ppc, arm64 Type: vcpu ioctl Parameters: struct kvm_guest_debug (in) Returns: 0 on success; -1 on error diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index bc738d2b8392..1b693cb2d5b2 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -301,13 +301,6 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) kvm_arm_set_running_vcpu(NULL); } -int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, - struct kvm_guest_debug *dbg) -{ - return -EINVAL; -} - - int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index d503fbb787d3..96e935bbc38c 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -290,3 +290,9 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, { return -EINVAL; } + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + return -EINVAL; +} diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 9535bd555d1d..0ba86775235d 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -331,3 +331,30 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, { return -EINVAL; } + +#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE) + +/** + * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging + * @kvm: pointer to the KVM struct + * @kvm_guest_debug: the ioctl data buffer + * + * This sets up and enables the VM for guest debugging. Userspace + * passes in a control flag to enable different debug types and + * potentially other architecture specific information in the rest of + * the structure. + */ +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) + return -EINVAL; + + if (dbg->control & KVM_GUESTDBG_ENABLE) { + vcpu->guest_debug = dbg->control; + } else { + /* If not enabled clear all flags */ + vcpu->guest_debug = 0; + } + return 0; +} -- cgit From 56c7f5e77f797fd0dcf2376ce1496f4238e6be33 Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:56 +0100 Subject: KVM: arm: introduce kvm_arm_init/setup/clear_debug MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is a precursor for later patches which will need to do more to setup debug state before entering the hyp.S switch code. The existing functionality for setting mdcr_el2 has been moved out of hyp.S and now uses the value kept in vcpu->arch.mdcr_el2. As the assembler used to previously mask and preserve MDCR_EL2.HPMN I've had to add a mechanism to save the value of mdcr_el2 as a per-cpu variable during the initialisation code. The kernel never sets this number so we are assuming the bootcode has set up the correct value here. This also moves the conditional setting of the TDA bit from the hyp code into the C code which is currently used for the lazy debug register context switch code. Signed-off-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_host.h | 4 ++ arch/arm/kvm/arm.c | 6 +++ arch/arm64/include/asm/kvm_asm.h | 2 + arch/arm64/include/asm/kvm_host.h | 5 +++ arch/arm64/kernel/asm-offsets.c | 1 + arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/debug.c | 81 +++++++++++++++++++++++++++++++++++++++ arch/arm64/kvm/hyp.S | 19 ++++----- 8 files changed, 108 insertions(+), 12 deletions(-) create mode 100644 arch/arm64/kvm/debug.c diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index e896d2c196e6..2b0bc8c57552 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -231,4 +231,8 @@ static inline void kvm_arch_sync_events(struct kvm *kvm) {} static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} +static inline void kvm_arm_init_debug(void) {} +static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} +static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} + #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 1b693cb2d5b2..77151b111d32 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -543,6 +543,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) continue; } + kvm_arm_setup_debug(vcpu); + /************************************************************** * Enter the guest */ @@ -557,6 +559,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) * Back from guest *************************************************************/ + kvm_arm_clear_debug(vcpu); + /* * We may have taken a host interrupt in HYP mode (ie * while executing the guest). This interrupt is still @@ -914,6 +918,8 @@ static void cpu_init_hyp_mode(void *dummy) vector_ptr = (unsigned long)__kvm_hyp_vector; __cpu_init_hyp_mode(boot_pgd_ptr, pgd_ptr, hyp_stack_ptr, vector_ptr); + + kvm_arm_init_debug(); } static int hyp_init_cpu_notify(struct notifier_block *self, diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 3c5fe685a2d6..f5e40dae291a 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -132,6 +132,8 @@ extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); extern u64 __vgic_v3_get_ich_vtr_el2(void); +extern u32 __kvm_get_mdcr_el2(void); + #endif #endif /* __ARM_KVM_ASM_H__ */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 2709db2a7eac..c90c6a41c448 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -103,6 +103,7 @@ struct kvm_vcpu_arch { /* HYP configuration */ u64 hcr_el2; + u32 mdcr_el2; /* Exception Information */ struct kvm_vcpu_fault_info fault; @@ -227,4 +228,8 @@ static inline void kvm_arch_sync_events(struct kvm *kvm) {} static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} +void kvm_arm_init_debug(void); +void kvm_arm_setup_debug(struct kvm_vcpu *vcpu); +void kvm_arm_clear_debug(struct kvm_vcpu *vcpu); + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index c99701a34d7b..5c900d49b906 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -117,6 +117,7 @@ int main(void) DEFINE(VCPU_HPFAR_EL2, offsetof(struct kvm_vcpu, arch.fault.hpfar_el2)); DEFINE(VCPU_DEBUG_FLAGS, offsetof(struct kvm_vcpu, arch.debug_flags)); DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2)); + DEFINE(VCPU_MDCR_EL2, offsetof(struct kvm_vcpu, arch.mdcr_el2)); DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines)); DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context)); DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl)); diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index f90f4aa7f88d..1949fe5f5424 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -17,7 +17,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o kvm-$(CONFIG_KVM_ARM_HOST) += emulate.o inject_fault.o regmap.o kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o -kvm-$(CONFIG_KVM_ARM_HOST) += guest.o reset.o sys_regs.o sys_regs_generic_v8.o +kvm-$(CONFIG_KVM_ARM_HOST) += guest.o debug.o reset.o sys_regs.o sys_regs_generic_v8.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v2.o diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c new file mode 100644 index 000000000000..faf0e1fdba9e --- /dev/null +++ b/arch/arm64/kvm/debug.c @@ -0,0 +1,81 @@ +/* + * Debug and Guest Debug support + * + * Copyright (C) 2015 - Linaro Ltd + * Author: Alex Bennée + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include + +#include + +static DEFINE_PER_CPU(u32, mdcr_el2); + +/** + * kvm_arm_init_debug - grab what we need for debug + * + * Currently the sole task of this function is to retrieve the initial + * value of mdcr_el2 so we can preserve MDCR_EL2.HPMN which has + * presumably been set-up by some knowledgeable bootcode. + * + * It is called once per-cpu during CPU hyp initialisation. + */ + +void kvm_arm_init_debug(void) +{ + __this_cpu_write(mdcr_el2, kvm_call_hyp(__kvm_get_mdcr_el2)); +} + + +/** + * kvm_arm_setup_debug - set up debug related stuff + * + * @vcpu: the vcpu pointer + * + * This is called before each entry into the hypervisor to setup any + * debug related registers. Currently this just ensures we will trap + * access to: + * - Performance monitors (MDCR_EL2_TPM/MDCR_EL2_TPMCR) + * - Debug ROM Address (MDCR_EL2_TDRA) + * - OS related registers (MDCR_EL2_TDOSA) + * + * Additionally, KVM only traps guest accesses to the debug registers if + * the guest is not actively using them (see the KVM_ARM64_DEBUG_DIRTY + * flag on vcpu->arch.debug_flags). Since the guest must not interfere + * with the hardware state when debugging the guest, we must ensure that + * trapping is enabled whenever we are debugging the guest using the + * debug registers. + */ + +void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) +{ + bool trap_debug = !(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY); + + vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; + vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | + MDCR_EL2_TPMCR | + MDCR_EL2_TDRA | + MDCR_EL2_TDOSA); + + /* Trap on access to debug registers? */ + if (trap_debug) + vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; + +} + +void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) +{ + /* Nothing to do yet */ +} diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 17a8fb14f428..b3176e6e51d1 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -770,17 +770,8 @@ mov x2, #(1 << 15) // Trap CP15 Cr=15 msr hstr_el2, x2 - mrs x2, mdcr_el2 - and x2, x2, #MDCR_EL2_HPMN_MASK - orr x2, x2, #(MDCR_EL2_TPM | MDCR_EL2_TPMCR) - orr x2, x2, #(MDCR_EL2_TDRA | MDCR_EL2_TDOSA) - - // Check for KVM_ARM64_DEBUG_DIRTY, and set debug to trap - // if not dirty. - ldr x3, [x0, #VCPU_DEBUG_FLAGS] - tbnz x3, #KVM_ARM64_DEBUG_DIRTY_SHIFT, 1f - orr x2, x2, #MDCR_EL2_TDA -1: + // Monitor Debug Config - see kvm_arm_setup_debug() + ldr x2, [x0, #VCPU_MDCR_EL2] msr mdcr_el2, x2 .endm @@ -1285,4 +1276,10 @@ ENTRY(__kvm_hyp_vector) ventry el1_error_invalid // Error 32-bit EL1 ENDPROC(__kvm_hyp_vector) + +ENTRY(__kvm_get_mdcr_el2) + mrs x0, mdcr_el2 + ret +ENDPROC(__kvm_get_mdcr_el2) + .popsection -- cgit From 4bd611ca60afa155bca25b40312ed61c4d46237f Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:57 +0100 Subject: KVM: arm64: guest debug, add SW break point support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds support for SW breakpoints inserted by userspace. We do this by trapping all guest software debug exceptions to the hypervisor (MDCR_EL2.TDE). The exit handler sets an exit reason of KVM_EXIT_DEBUG with the kvm_debug_exit_arch structure holding the exception syndrome information. It will be up to userspace to extract the PC (via GET_ONE_REG) and determine if the debug event was for a breakpoint it inserted. If not userspace will need to re-inject the correct exception restart the hypervisor to deliver the debug exception to the guest. Any other guest software debug exception (e.g. single step or HW assisted breakpoints) will cause an error and the VM to be killed. This is addressed by later patches which add support for the other debug types. Signed-off-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- Documentation/virtual/kvm/api.txt | 2 +- arch/arm64/kvm/debug.c | 3 +++ arch/arm64/kvm/guest.c | 2 +- arch/arm64/kvm/handle_exit.c | 36 ++++++++++++++++++++++++++++++++++++ 4 files changed, 41 insertions(+), 2 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 19adfd385882..0f498da354f2 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2693,7 +2693,7 @@ when running. Common control bits are: The top 16 bits of the control field are architecture specific control flags which can include the following: - - KVM_GUESTDBG_USE_SW_BP: using software breakpoints [x86] + - KVM_GUESTDBG_USE_SW_BP: using software breakpoints [x86, arm64] - KVM_GUESTDBG_USE_HW_BP: using hardware breakpoints [x86, s390] - KVM_GUESTDBG_INJECT_DB: inject DB type exception [x86] - KVM_GUESTDBG_INJECT_BP: inject BP type exception [x86] diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index faf0e1fdba9e..8d1bfa438310 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -73,6 +73,9 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) if (trap_debug) vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; + /* Trap breakpoints? */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP) + vcpu->arch.mdcr_el2 |= MDCR_EL2_TDE; } void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 0ba86775235d..22d22c54fd8d 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -332,7 +332,7 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, return -EINVAL; } -#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE) +#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) /** * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 524fa25671fc..27f38a9f9ea2 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -82,6 +82,40 @@ static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run) return 1; } +/** + * kvm_handle_guest_debug - handle a debug exception instruction + * + * @vcpu: the vcpu pointer + * @run: access to the kvm_run structure for results + * + * We route all debug exceptions through the same handler. If both the + * guest and host are using the same debug facilities it will be up to + * userspace to re-inject the correct exception for guest delivery. + * + * @return: 0 (while setting run->exit_reason), -1 for error + */ +static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + u32 hsr = kvm_vcpu_get_hsr(vcpu); + int ret = 0; + + run->exit_reason = KVM_EXIT_DEBUG; + run->debug.arch.hsr = hsr; + + switch (hsr >> ESR_ELx_EC_SHIFT) { + case ESR_ELx_EC_BKPT32: + case ESR_ELx_EC_BRK64: + break; + default: + kvm_err("%s: un-handled case hsr: %#08x\n", + __func__, (unsigned int) hsr); + ret = -1; + break; + } + + return ret; +} + static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_WFx] = kvm_handle_wfx, [ESR_ELx_EC_CP15_32] = kvm_handle_cp15_32, @@ -96,6 +130,8 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg, [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort, + [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, + [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, }; static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu) -- cgit From 337b99bf7edfb2044781447e7ca386edb1fdba9d Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:58 +0100 Subject: KVM: arm64: guest debug, add support for single-step MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds support for single-stepping the guest. To do this we need to manipulate the guests PSTATE.SS and MDSCR_EL1.SS bits to trigger stepping. We take care to preserve MDSCR_EL1 and trap access to it to ensure we don't affect the apparent state of the guest. As we have to enable trapping of all software debug exceptions we suppress the ability of the guest to single-step itself. If we didn't we would have to deal with the exception arriving while the guest was in kernelspace when the guest is expecting to single-step userspace. This is something we don't want to unwind in the kernel. Once the host is no longer debugging the guest its ability to single-step userspace is restored. Signed-off-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 11 +++++++ arch/arm64/kvm/debug.c | 68 ++++++++++++++++++++++++++++++++++++--- arch/arm64/kvm/guest.c | 4 ++- arch/arm64/kvm/handle_exit.c | 2 ++ 4 files changed, 80 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index c90c6a41c448..cfb675466e86 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -123,6 +123,17 @@ struct kvm_vcpu_arch { * here. */ + /* + * Guest registers we preserve during guest debugging. + * + * These shadow registers are updated by the kvm_handle_sys_reg + * trap handler if the guest accesses or updates them while we + * are using guest debug. + */ + struct { + u32 mdscr_el1; + } guest_debug_preserved; + /* Don't run the guest */ bool pause; diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index 8d1bfa438310..d439eb8f3239 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -19,10 +19,38 @@ #include +#include +#include #include +#include + +/* These are the bits of MDSCR_EL1 we may manipulate */ +#define MDSCR_EL1_DEBUG_MASK (DBG_MDSCR_SS | \ + DBG_MDSCR_KDE | \ + DBG_MDSCR_MDE) static DEFINE_PER_CPU(u32, mdcr_el2); +/** + * save/restore_guest_debug_regs + * + * For some debug operations we need to tweak some guest registers. As + * a result we need to save the state of those registers before we + * make those modifications. + * + * Guest access to MDSCR_EL1 is trapped by the hypervisor and handled + * after we have restored the preserved value to the main context. + */ +static void save_guest_debug_regs(struct kvm_vcpu *vcpu) +{ + vcpu->arch.guest_debug_preserved.mdscr_el1 = vcpu_sys_reg(vcpu, MDSCR_EL1); +} + +static void restore_guest_debug_regs(struct kvm_vcpu *vcpu) +{ + vcpu_sys_reg(vcpu, MDSCR_EL1) = vcpu->arch.guest_debug_preserved.mdscr_el1; +} + /** * kvm_arm_init_debug - grab what we need for debug * @@ -38,7 +66,6 @@ void kvm_arm_init_debug(void) __this_cpu_write(mdcr_el2, kvm_call_hyp(__kvm_get_mdcr_el2)); } - /** * kvm_arm_setup_debug - set up debug related stuff * @@ -73,12 +100,45 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) if (trap_debug) vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; - /* Trap breakpoints? */ - if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP) + /* Is Guest debugging in effect? */ + if (vcpu->guest_debug) { + /* Route all software debug exceptions to EL2 */ vcpu->arch.mdcr_el2 |= MDCR_EL2_TDE; + + /* Save guest debug state */ + save_guest_debug_regs(vcpu); + + /* + * Single Step (ARM ARM D2.12.3 The software step state + * machine) + * + * If we are doing Single Step we need to manipulate + * the guest's MDSCR_EL1.SS and PSTATE.SS. Once the + * step has occurred the hypervisor will trap the + * debug exception and we return to userspace. + * + * If the guest attempts to single step its userspace + * we would have to deal with a trapped exception + * while in the guest kernel. Because this would be + * hard to unwind we suppress the guest's ability to + * do so by masking MDSCR_EL.SS. + * + * This confuses guest debuggers which use + * single-step behind the scenes but everything + * returns to normal once the host is no longer + * debugging the system. + */ + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) { + *vcpu_cpsr(vcpu) |= DBG_SPSR_SS; + vcpu_sys_reg(vcpu, MDSCR_EL1) |= DBG_MDSCR_SS; + } else { + vcpu_sys_reg(vcpu, MDSCR_EL1) &= ~DBG_MDSCR_SS; + } + } } void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) { - /* Nothing to do yet */ + if (vcpu->guest_debug) + restore_guest_debug_regs(vcpu); } diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 22d22c54fd8d..48de4f4aaa1a 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -332,7 +332,9 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, return -EINVAL; } -#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP) +#define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | \ + KVM_GUESTDBG_USE_SW_BP | \ + KVM_GUESTDBG_SINGLESTEP) /** * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 27f38a9f9ea2..e9de13ed477e 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -103,6 +103,7 @@ static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) run->debug.arch.hsr = hsr; switch (hsr >> ESR_ELx_EC_SHIFT) { + case ESR_ELx_EC_SOFTSTP_LOW: case ESR_ELx_EC_BKPT32: case ESR_ELx_EC_BRK64: break; @@ -130,6 +131,7 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg, [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort, + [ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug, [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, }; -- cgit From e0a1b9a937dc6df9eb402af8966b5d617c7c6b34 Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:29:59 +0100 Subject: KVM: arm64: re-factor hyp.S debug register code MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is a pre-cursor to sharing the code with the guest debug support. This replaces the big macro that fishes data out of a fixed location with a more general helper macro to restore a set of debug registers. It uses macro substitution so it can be re-used for debug control and value registers. It does however rely on the debug registers being 64 bit aligned (as they happen to be in the hyp ABI). Signed-off-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp.S | 517 ++++++++++++++------------------------------------- 1 file changed, 138 insertions(+), 379 deletions(-) diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index b3176e6e51d1..8264f5b4817c 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -230,199 +230,52 @@ stp x24, x25, [x3, #160] .endm -.macro save_debug - // x2: base address for cpu context - // x3: tmp register - - mrs x26, id_aa64dfr0_el1 - ubfx x24, x26, #12, #4 // Extract BRPs - ubfx x25, x26, #20, #4 // Extract WRPs - mov w26, #15 - sub w24, w26, w24 // How many BPs to skip - sub w25, w26, w25 // How many WPs to skip - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 -1: - mrs x20, dbgbcr15_el1 - mrs x19, dbgbcr14_el1 - mrs x18, dbgbcr13_el1 - mrs x17, dbgbcr12_el1 - mrs x16, dbgbcr11_el1 - mrs x15, dbgbcr10_el1 - mrs x14, dbgbcr9_el1 - mrs x13, dbgbcr8_el1 - mrs x12, dbgbcr7_el1 - mrs x11, dbgbcr6_el1 - mrs x10, dbgbcr5_el1 - mrs x9, dbgbcr4_el1 - mrs x8, dbgbcr3_el1 - mrs x7, dbgbcr2_el1 - mrs x6, dbgbcr1_el1 - mrs x5, dbgbcr0_el1 - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 -1: - mrs x20, dbgbvr15_el1 - mrs x19, dbgbvr14_el1 - mrs x18, dbgbvr13_el1 - mrs x17, dbgbvr12_el1 - mrs x16, dbgbvr11_el1 - mrs x15, dbgbvr10_el1 - mrs x14, dbgbvr9_el1 - mrs x13, dbgbvr8_el1 - mrs x12, dbgbvr7_el1 - mrs x11, dbgbvr6_el1 - mrs x10, dbgbvr5_el1 - mrs x9, dbgbvr4_el1 - mrs x8, dbgbvr3_el1 - mrs x7, dbgbvr2_el1 - mrs x6, dbgbvr1_el1 - mrs x5, dbgbvr0_el1 - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - add x3, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 +.macro save_debug type + // x4: pointer to register set + // x5: number of registers to skip + // x6..x22 trashed + + adr x22, 1f + add x22, x22, x5, lsl #2 + br x22 1: - mrs x20, dbgwcr15_el1 - mrs x19, dbgwcr14_el1 - mrs x18, dbgwcr13_el1 - mrs x17, dbgwcr12_el1 - mrs x16, dbgwcr11_el1 - mrs x15, dbgwcr10_el1 - mrs x14, dbgwcr9_el1 - mrs x13, dbgwcr8_el1 - mrs x12, dbgwcr7_el1 - mrs x11, dbgwcr6_el1 - mrs x10, dbgwcr5_el1 - mrs x9, dbgwcr4_el1 - mrs x8, dbgwcr3_el1 - mrs x7, dbgwcr2_el1 - mrs x6, dbgwcr1_el1 - mrs x5, dbgwcr0_el1 - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - add x3, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 + mrs x21, \type\()15_el1 + mrs x20, \type\()14_el1 + mrs x19, \type\()13_el1 + mrs x18, \type\()12_el1 + mrs x17, \type\()11_el1 + mrs x16, \type\()10_el1 + mrs x15, \type\()9_el1 + mrs x14, \type\()8_el1 + mrs x13, \type\()7_el1 + mrs x12, \type\()6_el1 + mrs x11, \type\()5_el1 + mrs x10, \type\()4_el1 + mrs x9, \type\()3_el1 + mrs x8, \type\()2_el1 + mrs x7, \type\()1_el1 + mrs x6, \type\()0_el1 + + adr x22, 1f + add x22, x22, x5, lsl #2 + br x22 1: - mrs x20, dbgwvr15_el1 - mrs x19, dbgwvr14_el1 - mrs x18, dbgwvr13_el1 - mrs x17, dbgwvr12_el1 - mrs x16, dbgwvr11_el1 - mrs x15, dbgwvr10_el1 - mrs x14, dbgwvr9_el1 - mrs x13, dbgwvr8_el1 - mrs x12, dbgwvr7_el1 - mrs x11, dbgwvr6_el1 - mrs x10, dbgwvr5_el1 - mrs x9, dbgwvr4_el1 - mrs x8, dbgwvr3_el1 - mrs x7, dbgwvr2_el1 - mrs x6, dbgwvr1_el1 - mrs x5, dbgwvr0_el1 - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 - -1: - str x20, [x3, #(15 * 8)] - str x19, [x3, #(14 * 8)] - str x18, [x3, #(13 * 8)] - str x17, [x3, #(12 * 8)] - str x16, [x3, #(11 * 8)] - str x15, [x3, #(10 * 8)] - str x14, [x3, #(9 * 8)] - str x13, [x3, #(8 * 8)] - str x12, [x3, #(7 * 8)] - str x11, [x3, #(6 * 8)] - str x10, [x3, #(5 * 8)] - str x9, [x3, #(4 * 8)] - str x8, [x3, #(3 * 8)] - str x7, [x3, #(2 * 8)] - str x6, [x3, #(1 * 8)] - str x5, [x3, #(0 * 8)] - - mrs x21, mdccint_el1 - str x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] + str x21, [x4, #(15 * 8)] + str x20, [x4, #(14 * 8)] + str x19, [x4, #(13 * 8)] + str x18, [x4, #(12 * 8)] + str x17, [x4, #(11 * 8)] + str x16, [x4, #(10 * 8)] + str x15, [x4, #(9 * 8)] + str x14, [x4, #(8 * 8)] + str x13, [x4, #(7 * 8)] + str x12, [x4, #(6 * 8)] + str x11, [x4, #(5 * 8)] + str x10, [x4, #(4 * 8)] + str x9, [x4, #(3 * 8)] + str x8, [x4, #(2 * 8)] + str x7, [x4, #(1 * 8)] + str x6, [x4, #(0 * 8)] .endm .macro restore_sysregs @@ -467,195 +320,52 @@ msr mdscr_el1, x25 .endm -.macro restore_debug - // x2: base address for cpu context - // x3: tmp register - - mrs x26, id_aa64dfr0_el1 - ubfx x24, x26, #12, #4 // Extract BRPs - ubfx x25, x26, #20, #4 // Extract WRPs - mov w26, #15 - sub w24, w26, w24 // How many BPs to skip - sub w25, w26, w25 // How many WPs to skip - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) +.macro restore_debug type + // x4: pointer to register set + // x5: number of registers to skip + // x6..x22 trashed - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 + adr x22, 1f + add x22, x22, x5, lsl #2 + br x22 1: - ldr x20, [x3, #(15 * 8)] - ldr x19, [x3, #(14 * 8)] - ldr x18, [x3, #(13 * 8)] - ldr x17, [x3, #(12 * 8)] - ldr x16, [x3, #(11 * 8)] - ldr x15, [x3, #(10 * 8)] - ldr x14, [x3, #(9 * 8)] - ldr x13, [x3, #(8 * 8)] - ldr x12, [x3, #(7 * 8)] - ldr x11, [x3, #(6 * 8)] - ldr x10, [x3, #(5 * 8)] - ldr x9, [x3, #(4 * 8)] - ldr x8, [x3, #(3 * 8)] - ldr x7, [x3, #(2 * 8)] - ldr x6, [x3, #(1 * 8)] - ldr x5, [x3, #(0 * 8)] - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 + ldr x21, [x4, #(15 * 8)] + ldr x20, [x4, #(14 * 8)] + ldr x19, [x4, #(13 * 8)] + ldr x18, [x4, #(12 * 8)] + ldr x17, [x4, #(11 * 8)] + ldr x16, [x4, #(10 * 8)] + ldr x15, [x4, #(9 * 8)] + ldr x14, [x4, #(8 * 8)] + ldr x13, [x4, #(7 * 8)] + ldr x12, [x4, #(6 * 8)] + ldr x11, [x4, #(5 * 8)] + ldr x10, [x4, #(4 * 8)] + ldr x9, [x4, #(3 * 8)] + ldr x8, [x4, #(2 * 8)] + ldr x7, [x4, #(1 * 8)] + ldr x6, [x4, #(0 * 8)] + + adr x22, 1f + add x22, x22, x5, lsl #2 + br x22 1: - msr dbgbcr15_el1, x20 - msr dbgbcr14_el1, x19 - msr dbgbcr13_el1, x18 - msr dbgbcr12_el1, x17 - msr dbgbcr11_el1, x16 - msr dbgbcr10_el1, x15 - msr dbgbcr9_el1, x14 - msr dbgbcr8_el1, x13 - msr dbgbcr7_el1, x12 - msr dbgbcr6_el1, x11 - msr dbgbcr5_el1, x10 - msr dbgbcr4_el1, x9 - msr dbgbcr3_el1, x8 - msr dbgbcr2_el1, x7 - msr dbgbcr1_el1, x6 - msr dbgbcr0_el1, x5 - - add x3, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 -1: - ldr x20, [x3, #(15 * 8)] - ldr x19, [x3, #(14 * 8)] - ldr x18, [x3, #(13 * 8)] - ldr x17, [x3, #(12 * 8)] - ldr x16, [x3, #(11 * 8)] - ldr x15, [x3, #(10 * 8)] - ldr x14, [x3, #(9 * 8)] - ldr x13, [x3, #(8 * 8)] - ldr x12, [x3, #(7 * 8)] - ldr x11, [x3, #(6 * 8)] - ldr x10, [x3, #(5 * 8)] - ldr x9, [x3, #(4 * 8)] - ldr x8, [x3, #(3 * 8)] - ldr x7, [x3, #(2 * 8)] - ldr x6, [x3, #(1 * 8)] - ldr x5, [x3, #(0 * 8)] - - adr x26, 1f - add x26, x26, x24, lsl #2 - br x26 -1: - msr dbgbvr15_el1, x20 - msr dbgbvr14_el1, x19 - msr dbgbvr13_el1, x18 - msr dbgbvr12_el1, x17 - msr dbgbvr11_el1, x16 - msr dbgbvr10_el1, x15 - msr dbgbvr9_el1, x14 - msr dbgbvr8_el1, x13 - msr dbgbvr7_el1, x12 - msr dbgbvr6_el1, x11 - msr dbgbvr5_el1, x10 - msr dbgbvr4_el1, x9 - msr dbgbvr3_el1, x8 - msr dbgbvr2_el1, x7 - msr dbgbvr1_el1, x6 - msr dbgbvr0_el1, x5 - - add x3, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 -1: - ldr x20, [x3, #(15 * 8)] - ldr x19, [x3, #(14 * 8)] - ldr x18, [x3, #(13 * 8)] - ldr x17, [x3, #(12 * 8)] - ldr x16, [x3, #(11 * 8)] - ldr x15, [x3, #(10 * 8)] - ldr x14, [x3, #(9 * 8)] - ldr x13, [x3, #(8 * 8)] - ldr x12, [x3, #(7 * 8)] - ldr x11, [x3, #(6 * 8)] - ldr x10, [x3, #(5 * 8)] - ldr x9, [x3, #(4 * 8)] - ldr x8, [x3, #(3 * 8)] - ldr x7, [x3, #(2 * 8)] - ldr x6, [x3, #(1 * 8)] - ldr x5, [x3, #(0 * 8)] - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 -1: - msr dbgwcr15_el1, x20 - msr dbgwcr14_el1, x19 - msr dbgwcr13_el1, x18 - msr dbgwcr12_el1, x17 - msr dbgwcr11_el1, x16 - msr dbgwcr10_el1, x15 - msr dbgwcr9_el1, x14 - msr dbgwcr8_el1, x13 - msr dbgwcr7_el1, x12 - msr dbgwcr6_el1, x11 - msr dbgwcr5_el1, x10 - msr dbgwcr4_el1, x9 - msr dbgwcr3_el1, x8 - msr dbgwcr2_el1, x7 - msr dbgwcr1_el1, x6 - msr dbgwcr0_el1, x5 - - add x3, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 -1: - ldr x20, [x3, #(15 * 8)] - ldr x19, [x3, #(14 * 8)] - ldr x18, [x3, #(13 * 8)] - ldr x17, [x3, #(12 * 8)] - ldr x16, [x3, #(11 * 8)] - ldr x15, [x3, #(10 * 8)] - ldr x14, [x3, #(9 * 8)] - ldr x13, [x3, #(8 * 8)] - ldr x12, [x3, #(7 * 8)] - ldr x11, [x3, #(6 * 8)] - ldr x10, [x3, #(5 * 8)] - ldr x9, [x3, #(4 * 8)] - ldr x8, [x3, #(3 * 8)] - ldr x7, [x3, #(2 * 8)] - ldr x6, [x3, #(1 * 8)] - ldr x5, [x3, #(0 * 8)] - - adr x26, 1f - add x26, x26, x25, lsl #2 - br x26 -1: - msr dbgwvr15_el1, x20 - msr dbgwvr14_el1, x19 - msr dbgwvr13_el1, x18 - msr dbgwvr12_el1, x17 - msr dbgwvr11_el1, x16 - msr dbgwvr10_el1, x15 - msr dbgwvr9_el1, x14 - msr dbgwvr8_el1, x13 - msr dbgwvr7_el1, x12 - msr dbgwvr6_el1, x11 - msr dbgwvr5_el1, x10 - msr dbgwvr4_el1, x9 - msr dbgwvr3_el1, x8 - msr dbgwvr2_el1, x7 - msr dbgwvr1_el1, x6 - msr dbgwvr0_el1, x5 - - ldr x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] - msr mdccint_el1, x21 + msr \type\()15_el1, x21 + msr \type\()14_el1, x20 + msr \type\()13_el1, x19 + msr \type\()12_el1, x18 + msr \type\()11_el1, x17 + msr \type\()10_el1, x16 + msr \type\()9_el1, x15 + msr \type\()8_el1, x14 + msr \type\()7_el1, x13 + msr \type\()6_el1, x12 + msr \type\()5_el1, x11 + msr \type\()4_el1, x10 + msr \type\()3_el1, x9 + msr \type\()2_el1, x8 + msr \type\()1_el1, x7 + msr \type\()0_el1, x6 .endm .macro skip_32bit_state tmp, target @@ -883,12 +593,61 @@ __restore_sysregs: restore_sysregs ret +/* Save debug state */ __save_debug: - save_debug + // x2: ptr to CPU context + // x4/x5/x6-22/x24-26: trashed + + mrs x26, id_aa64dfr0_el1 + ubfx x24, x26, #12, #4 // Extract BRPs + ubfx x25, x26, #20, #4 // Extract WRPs + mov w26, #15 + sub w24, w26, w24 // How many BPs to skip + sub w25, w26, w25 // How many WPs to skip + + mov x5, x24 + add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + save_debug dbgbcr + add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + save_debug dbgbvr + + mov x5, x25 + add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + save_debug dbgwcr + add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + save_debug dbgwvr + + mrs x21, mdccint_el1 + str x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] ret +/* Restore debug state */ __restore_debug: - restore_debug + // x2: ptr to CPU context + // x4/x5/x6-22/x24-26: trashed + + mrs x26, id_aa64dfr0_el1 + ubfx x24, x26, #12, #4 // Extract BRPs + ubfx x25, x26, #20, #4 // Extract WRPs + mov w26, #15 + sub w24, w26, w24 // How many BPs to skip + sub w25, w26, w25 // How many WPs to skip + + mov x5, x24 + add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + restore_debug dbgbcr + add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + restore_debug dbgbvr + + mov x5, x25 + add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + restore_debug dbgwcr + add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + restore_debug dbgwvr + + ldr x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] + msr mdccint_el1, x21 + ret __save_fpsimd: -- cgit From 84e690bfbed1d1ecb45d8eccd4c7b6c8e878da1c Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:30:00 +0100 Subject: KVM: arm64: introduce vcpu->arch.debug_ptr MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This introduces a level of indirection for the debug registers. Instead of using the sys_regs[] directly we store registers in a structure in the vcpu. The new kvm_arm_reset_debug_ptr() sets the debug ptr to the guest context. Because we no longer give the sys_regs offset for the sys_reg_desc->reg field, but instead the index into a debug-specific struct we need to add a number of additional trap functions for each register. Also as the generic generic user-space access code no longer works we have introduced a new pair of function pointers to the sys_reg_desc structure to override the generic code when needed. Reviewed-by: Christoffer Dall Signed-off-by: Alex Bennée Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_host.h | 1 + arch/arm/kvm/arm.c | 2 + arch/arm64/include/asm/kvm_asm.h | 24 ++-- arch/arm64/include/asm/kvm_host.h | 17 ++- arch/arm64/kernel/asm-offsets.c | 6 + arch/arm64/kvm/debug.c | 9 ++ arch/arm64/kvm/hyp.S | 24 ++-- arch/arm64/kvm/sys_regs.c | 274 +++++++++++++++++++++++++++++++++++--- arch/arm64/kvm/sys_regs.h | 6 + 9 files changed, 316 insertions(+), 47 deletions(-) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 2b0bc8c57552..dcba0fa5176e 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -234,5 +234,6 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} static inline void kvm_arm_init_debug(void) {} static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} +static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {} #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 77151b111d32..9ce5cf02ed17 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -278,6 +278,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) /* Set up the timer */ kvm_timer_vcpu_init(vcpu); + kvm_arm_reset_debug_ptr(vcpu); + return 0; } diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index f5e40dae291a..67fa0de3d483 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -46,24 +46,16 @@ #define CNTKCTL_EL1 20 /* Timer Control Register (EL1) */ #define PAR_EL1 21 /* Physical Address Register */ #define MDSCR_EL1 22 /* Monitor Debug System Control Register */ -#define DBGBCR0_EL1 23 /* Debug Breakpoint Control Registers (0-15) */ -#define DBGBCR15_EL1 38 -#define DBGBVR0_EL1 39 /* Debug Breakpoint Value Registers (0-15) */ -#define DBGBVR15_EL1 54 -#define DBGWCR0_EL1 55 /* Debug Watchpoint Control Registers (0-15) */ -#define DBGWCR15_EL1 70 -#define DBGWVR0_EL1 71 /* Debug Watchpoint Value Registers (0-15) */ -#define DBGWVR15_EL1 86 -#define MDCCINT_EL1 87 /* Monitor Debug Comms Channel Interrupt Enable Reg */ +#define MDCCINT_EL1 23 /* Monitor Debug Comms Channel Interrupt Enable Reg */ /* 32bit specific registers. Keep them at the end of the range */ -#define DACR32_EL2 88 /* Domain Access Control Register */ -#define IFSR32_EL2 89 /* Instruction Fault Status Register */ -#define FPEXC32_EL2 90 /* Floating-Point Exception Control Register */ -#define DBGVCR32_EL2 91 /* Debug Vector Catch Register */ -#define TEECR32_EL1 92 /* ThumbEE Configuration Register */ -#define TEEHBR32_EL1 93 /* ThumbEE Handler Base Register */ -#define NR_SYS_REGS 94 +#define DACR32_EL2 24 /* Domain Access Control Register */ +#define IFSR32_EL2 25 /* Instruction Fault Status Register */ +#define FPEXC32_EL2 26 /* Floating-Point Exception Control Register */ +#define DBGVCR32_EL2 27 /* Debug Vector Catch Register */ +#define TEECR32_EL1 28 /* ThumbEE Configuration Register */ +#define TEEHBR32_EL1 29 /* ThumbEE Handler Base Register */ +#define NR_SYS_REGS 30 /* 32bit mapping */ #define c0_MPIDR (MPIDR_EL1 * 2) /* MultiProcessor ID Register */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index cfb675466e86..9b99402b14df 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -108,11 +108,25 @@ struct kvm_vcpu_arch { /* Exception Information */ struct kvm_vcpu_fault_info fault; - /* Debug state */ + /* Guest debug state */ u64 debug_flags; + /* + * We maintain more than a single set of debug registers to support + * debugging the guest from the host and to maintain separate host and + * guest state during world switches. vcpu_debug_state are the debug + * registers of the vcpu as the guest sees them. host_debug_state are + * the host registers which are saved and restored during world switches. + * + * debug_ptr points to the set of debug registers that should be loaded + * onto the hardware when running the guest. + */ + struct kvm_guest_debug_arch *debug_ptr; + struct kvm_guest_debug_arch vcpu_debug_state; + /* Pointer to host CPU context */ kvm_cpu_context_t *host_cpu_context; + struct kvm_guest_debug_arch host_debug_state; /* VGIC state */ struct vgic_cpu vgic_cpu; @@ -242,5 +256,6 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} void kvm_arm_init_debug(void); void kvm_arm_setup_debug(struct kvm_vcpu *vcpu); void kvm_arm_clear_debug(struct kvm_vcpu *vcpu); +void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu); #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 5c900d49b906..d88630899a24 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -116,10 +116,16 @@ int main(void) DEFINE(VCPU_FAR_EL2, offsetof(struct kvm_vcpu, arch.fault.far_el2)); DEFINE(VCPU_HPFAR_EL2, offsetof(struct kvm_vcpu, arch.fault.hpfar_el2)); DEFINE(VCPU_DEBUG_FLAGS, offsetof(struct kvm_vcpu, arch.debug_flags)); + DEFINE(VCPU_DEBUG_PTR, offsetof(struct kvm_vcpu, arch.debug_ptr)); + DEFINE(DEBUG_BCR, offsetof(struct kvm_guest_debug_arch, dbg_bcr)); + DEFINE(DEBUG_BVR, offsetof(struct kvm_guest_debug_arch, dbg_bvr)); + DEFINE(DEBUG_WCR, offsetof(struct kvm_guest_debug_arch, dbg_wcr)); + DEFINE(DEBUG_WVR, offsetof(struct kvm_guest_debug_arch, dbg_wvr)); DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2)); DEFINE(VCPU_MDCR_EL2, offsetof(struct kvm_vcpu, arch.mdcr_el2)); DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines)); DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context)); + DEFINE(VCPU_HOST_DEBUG_STATE, offsetof(struct kvm_vcpu, arch.host_debug_state)); DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl)); DEFINE(VCPU_TIMER_CNTV_CVAL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval)); DEFINE(KVM_TIMER_CNTVOFF, offsetof(struct kvm, arch.timer.cntvoff)); diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index d439eb8f3239..e0947b77faaa 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -66,6 +66,15 @@ void kvm_arm_init_debug(void) __this_cpu_write(mdcr_el2, kvm_call_hyp(__kvm_get_mdcr_el2)); } +/** + * kvm_arm_reset_debug_ptr - reset the debug ptr to point to the vcpu state + */ + +void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) +{ + vcpu->arch.debug_ptr = &vcpu->arch.vcpu_debug_state; +} + /** * kvm_arm_setup_debug - set up debug related stuff * diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 8264f5b4817c..d93c0a23630e 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -596,6 +596,7 @@ __restore_sysregs: /* Save debug state */ __save_debug: // x2: ptr to CPU context + // x3: ptr to debug reg struct // x4/x5/x6-22/x24-26: trashed mrs x26, id_aa64dfr0_el1 @@ -606,15 +607,15 @@ __save_debug: sub w25, w26, w25 // How many WPs to skip mov x5, x24 - add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + add x4, x3, #DEBUG_BCR save_debug dbgbcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + add x4, x3, #DEBUG_BVR save_debug dbgbvr mov x5, x25 - add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + add x4, x3, #DEBUG_WCR save_debug dbgwcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + add x4, x3, #DEBUG_WVR save_debug dbgwvr mrs x21, mdccint_el1 @@ -624,6 +625,7 @@ __save_debug: /* Restore debug state */ __restore_debug: // x2: ptr to CPU context + // x3: ptr to debug reg struct // x4/x5/x6-22/x24-26: trashed mrs x26, id_aa64dfr0_el1 @@ -634,15 +636,15 @@ __restore_debug: sub w25, w26, w25 // How many WPs to skip mov x5, x24 - add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + add x4, x3, #DEBUG_BCR restore_debug dbgbcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + add x4, x3, #DEBUG_BVR restore_debug dbgbvr mov x5, x25 - add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + add x4, x3, #DEBUG_WCR restore_debug dbgwcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + add x4, x3, #DEBUG_WVR restore_debug dbgwvr ldr x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] @@ -682,6 +684,7 @@ ENTRY(__kvm_vcpu_run) bl __save_sysregs compute_debug_state 1f + add x3, x0, #VCPU_HOST_DEBUG_STATE bl __save_debug 1: activate_traps @@ -697,6 +700,8 @@ ENTRY(__kvm_vcpu_run) bl __restore_fpsimd skip_debug_state x3, 1f + ldr x3, [x0, #VCPU_DEBUG_PTR] + kern_hyp_va x3 bl __restore_debug 1: restore_guest_32bit_state @@ -717,6 +722,8 @@ __kvm_vcpu_return: bl __save_sysregs skip_debug_state x3, 1f + ldr x3, [x0, #VCPU_DEBUG_PTR] + kern_hyp_va x3 bl __save_debug 1: save_guest_32bit_state @@ -739,6 +746,7 @@ __kvm_vcpu_return: // already been saved. Note that we nuke the whole 64bit word. // If we ever add more flags, we'll have to be more careful... str xzr, [x0, #VCPU_DEBUG_FLAGS] + add x3, x0, #VCPU_HOST_DEBUG_STATE bl __restore_debug 1: restore_host_regs diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index c370b4014799..158bae7c52cc 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -211,6 +211,203 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu, return true; } +/* + * reg_to_dbg/dbg_to_reg + * + * A 32 bit write to a debug register leave top bits alone + * A 32 bit read from a debug register only returns the bottom bits + * + * All writes will set the KVM_ARM64_DEBUG_DIRTY flag to ensure the + * hyp.S code switches between host and guest values in future. + */ +static inline void reg_to_dbg(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + u64 *dbg_reg) +{ + u64 val = *vcpu_reg(vcpu, p->Rt); + + if (p->is_32bit) { + val &= 0xffffffffUL; + val |= ((*dbg_reg >> 32) << 32); + } + + *dbg_reg = val; + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; +} + +static inline void dbg_to_reg(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + u64 *dbg_reg) +{ + u64 val = *dbg_reg; + + if (p->is_32bit) + val &= 0xffffffffUL; + + *vcpu_reg(vcpu, p->Rt) = val; +} + +static inline bool trap_bvr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static int get_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_bvr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg] = rd->val; +} + +static inline bool trap_bcr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + + return 0; +} + +static int get_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_bcr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg] = rd->val; +} + +static inline bool trap_wvr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static int get_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_wvr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg] = rd->val; +} + +static inline bool trap_wcr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static int get_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_wcr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg] = rd->val; +} + static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { u64 amair; @@ -240,16 +437,16 @@ static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) #define DBG_BCR_BVR_WCR_WVR_EL1(n) \ /* DBGBVRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b100), \ - trap_debug_regs, reset_val, (DBGBVR0_EL1 + (n)), 0 }, \ + trap_bvr, reset_bvr, n, 0, get_bvr, set_bvr }, \ /* DBGBCRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b101), \ - trap_debug_regs, reset_val, (DBGBCR0_EL1 + (n)), 0 }, \ + trap_bcr, reset_bcr, n, 0, get_bcr, set_bcr }, \ /* DBGWVRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b110), \ - trap_debug_regs, reset_val, (DBGWVR0_EL1 + (n)), 0 }, \ + trap_wvr, reset_wvr, n, 0, get_wvr, set_wvr }, \ /* DBGWCRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111), \ - trap_debug_regs, reset_val, (DBGWCR0_EL1 + (n)), 0 } + trap_wcr, reset_wcr, n, 0, get_wcr, set_wcr } /* * Architected system registers. @@ -516,28 +713,55 @@ static bool trap_debug32(struct kvm_vcpu *vcpu, return true; } -#define DBG_BCR_BVR_WCR_WVR(n) \ - /* DBGBVRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_debug32, \ - NULL, (cp14_DBGBVR0 + (n) * 2) }, \ - /* DBGBCRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_debug32, \ - NULL, (cp14_DBGBCR0 + (n) * 2) }, \ - /* DBGWVRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_debug32, \ - NULL, (cp14_DBGWVR0 + (n) * 2) }, \ - /* DBGWCRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_debug32, \ - NULL, (cp14_DBGWCR0 + (n) * 2) } - -#define DBGBXVR(n) \ - { Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_debug32, \ - NULL, cp14_DBGBXVR0 + n * 2 } +/* AArch32 debug register mappings + * + * AArch32 DBGBVRn is mapped to DBGBVRn_EL1[31:0] + * AArch32 DBGBXVRn is mapped to DBGBVRn_EL1[63:32] + * + * All control registers and watchpoint value registers are mapped to + * the lower 32 bits of their AArch64 equivalents. We share the trap + * handlers with the above AArch64 code which checks what mode the + * system is in. + */ + +static inline bool trap_xvr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (p->is_write) { + u64 val = *dbg_reg; + + val &= 0xffffffffUL; + val |= *vcpu_reg(vcpu, p->Rt) << 32; + *dbg_reg = val; + + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; + } else { + *vcpu_reg(vcpu, p->Rt) = *dbg_reg >> 32; + } + + return true; +} + +#define DBG_BCR_BVR_WCR_WVR(n) \ + /* DBGBVRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_bvr, NULL, n }, \ + /* DBGBCRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_bcr, NULL, n }, \ + /* DBGWVRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_wvr, NULL, n }, \ + /* DBGWCRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_wcr, NULL, n } + +#define DBGBXVR(n) \ + { Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_xvr, NULL, n } /* * Trapped cp14 registers. We generally ignore most of the external * debug, on the principle that they don't really make sense to a - * guest. Revisit this one day, whould this principle change. + * guest. Revisit this one day, would this principle change. */ static const struct sys_reg_desc cp14_regs[] = { /* DBGIDR */ @@ -1303,6 +1527,9 @@ int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg if (!r) return get_invariant_sys_reg(reg->id, uaddr); + if (r->get_user) + return (r->get_user)(vcpu, r, reg, uaddr); + return reg_to_user(uaddr, &vcpu_sys_reg(vcpu, r->reg), reg->id); } @@ -1321,6 +1548,9 @@ int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg if (!r) return set_invariant_sys_reg(reg->id, uaddr); + if (r->set_user) + return (r->set_user)(vcpu, r, reg, uaddr); + return reg_from_user(&vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id); } diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h index d411e251412c..eaa324e4db4d 100644 --- a/arch/arm64/kvm/sys_regs.h +++ b/arch/arm64/kvm/sys_regs.h @@ -55,6 +55,12 @@ struct sys_reg_desc { /* Value (usually reset value) */ u64 val; + + /* Custom get/set_user functions, fallback to generic if NULL */ + int (*get_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr); + int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr); }; static inline void print_sys_reg_instr(const struct sys_reg_params *p) -- cgit From 5540546bc93b49f98a0466fe3f96615286c76574 Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:30:01 +0100 Subject: KVM: arm64: guest debug, HW assisted debug support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds support for userspace to control the HW debug registers for guest debug. In the debug ioctl we copy an IMPDEF registers into a new register set called host_debug_state. We use the recently introduced vcpu parameter debug_ptr to select which register set is copied into the real registers when world switch occurs. I've made some helper functions from hw_breakpoint.c more widely available for re-use. As with single step we need to tweak the guest registers to enable the exceptions so we need to save and restore those bits. Two new capabilities have been added to the KVM_EXTENSION ioctl to allow userspace to query the number of hardware break and watch points available on the host hardware. Signed-off-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- include/uapi/linux/kvm.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 4ab3c6a8d563..a1e08e7bbf20 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -820,6 +820,8 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_DISABLE_QUIRKS 116 #define KVM_CAP_X86_SMM 117 #define KVM_CAP_MULTI_ADDRESS_SPACE 118 +#define KVM_CAP_GUEST_DEBUG_HW_BPS 119 +#define KVM_CAP_GUEST_DEBUG_HW_WPS 120 #ifdef KVM_CAP_IRQ_ROUTING -- cgit From 834bf88726f0f11ddc7ff9679fc9458654c01a12 Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:30:02 +0100 Subject: KVM: arm64: enable KVM_CAP_SET_GUEST_DEBUG MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Finally advertise the KVM capability for SET_GUEST_DEBUG. Once arm support is added this check can be moved to the common kvm_vm_ioctl_check_extension() code. Signed-off-by: Alex Bennée Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier --- Documentation/virtual/kvm/api.txt | 7 +++++- arch/arm64/include/asm/hw_breakpoint.h | 14 ++++++++++++ arch/arm64/include/asm/kvm_host.h | 6 ++++- arch/arm64/kernel/hw_breakpoint.c | 12 ---------- arch/arm64/kvm/debug.c | 40 +++++++++++++++++++++++++++++----- arch/arm64/kvm/guest.c | 7 ++++++ arch/arm64/kvm/handle_exit.c | 6 +++++ arch/arm64/kvm/reset.c | 16 ++++++++++++++ 8 files changed, 89 insertions(+), 19 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 0f498da354f2..35affb5d9456 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2694,7 +2694,7 @@ The top 16 bits of the control field are architecture specific control flags which can include the following: - KVM_GUESTDBG_USE_SW_BP: using software breakpoints [x86, arm64] - - KVM_GUESTDBG_USE_HW_BP: using hardware breakpoints [x86, s390] + - KVM_GUESTDBG_USE_HW_BP: using hardware breakpoints [x86, s390, arm64] - KVM_GUESTDBG_INJECT_DB: inject DB type exception [x86] - KVM_GUESTDBG_INJECT_BP: inject BP type exception [x86] - KVM_GUESTDBG_EXIT_PENDING: trigger an immediate guest exit [s390] @@ -2709,6 +2709,11 @@ updated to the correct (supplied) values. The second part of the structure is architecture specific and typically contains a set of debug registers. +For arm64 the number of debug registers is implementation defined and +can be determined by querying the KVM_CAP_GUEST_DEBUG_HW_BPS and +KVM_CAP_GUEST_DEBUG_HW_WPS capabilities which return a positive number +indicating the number of supported registers. + When debug events exit the main run loop with the reason KVM_EXIT_DEBUG with the kvm_debug_exit_arch part of the kvm_run structure containing architecture specific debug information. diff --git a/arch/arm64/include/asm/hw_breakpoint.h b/arch/arm64/include/asm/hw_breakpoint.h index 52b484b6aa1a..4c47cb2fbb52 100644 --- a/arch/arm64/include/asm/hw_breakpoint.h +++ b/arch/arm64/include/asm/hw_breakpoint.h @@ -16,6 +16,8 @@ #ifndef __ASM_HW_BREAKPOINT_H #define __ASM_HW_BREAKPOINT_H +#include + #ifdef __KERNEL__ struct arch_hw_breakpoint_ctrl { @@ -132,5 +134,17 @@ static inline void ptrace_hw_copy_thread(struct task_struct *task) extern struct pmu perf_ops_bp; +/* Determine number of BRP registers available. */ +static inline int get_num_brps(void) +{ + return ((read_cpuid(ID_AA64DFR0_EL1) >> 12) & 0xf) + 1; +} + +/* Determine number of WRP registers available. */ +static inline int get_num_wrps(void) +{ + return ((read_cpuid(ID_AA64DFR0_EL1) >> 20) & 0xf) + 1; +} + #endif /* __KERNEL__ */ #endif /* __ASM_BREAKPOINT_H */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 9b99402b14df..409217f48456 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -116,13 +116,17 @@ struct kvm_vcpu_arch { * debugging the guest from the host and to maintain separate host and * guest state during world switches. vcpu_debug_state are the debug * registers of the vcpu as the guest sees them. host_debug_state are - * the host registers which are saved and restored during world switches. + * the host registers which are saved and restored during + * world switches. external_debug_state contains the debug + * values we want to debug the guest. This is set via the + * KVM_SET_GUEST_DEBUG ioctl. * * debug_ptr points to the set of debug registers that should be loaded * onto the hardware when running the guest. */ struct kvm_guest_debug_arch *debug_ptr; struct kvm_guest_debug_arch vcpu_debug_state; + struct kvm_guest_debug_arch external_debug_state; /* Pointer to host CPU context */ kvm_cpu_context_t *host_cpu_context; diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index 7a1a5da6c8c1..77bee00bd7ea 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -48,18 +48,6 @@ static DEFINE_PER_CPU(int, stepping_kernel_bp); static int core_num_brps; static int core_num_wrps; -/* Determine number of BRP registers available. */ -static int get_num_brps(void) -{ - return ((read_cpuid(ID_AA64DFR0_EL1) >> 12) & 0xf) + 1; -} - -/* Determine number of WRP registers available. */ -static int get_num_wrps(void) -{ - return ((read_cpuid(ID_AA64DFR0_EL1) >> 20) & 0xf) + 1; -} - int hw_breakpoint_slots(int type) { /* diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index e0947b77faaa..4a99e54d7f3d 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -105,10 +105,6 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) MDCR_EL2_TDRA | MDCR_EL2_TDOSA); - /* Trap on access to debug registers? */ - if (trap_debug) - vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; - /* Is Guest debugging in effect? */ if (vcpu->guest_debug) { /* Route all software debug exceptions to EL2 */ @@ -143,11 +139,45 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) } else { vcpu_sys_reg(vcpu, MDSCR_EL1) &= ~DBG_MDSCR_SS; } + + /* + * HW Breakpoints and watchpoints + * + * We simply switch the debug_ptr to point to our new + * external_debug_state which has been populated by the + * debug ioctl. The existing KVM_ARM64_DEBUG_DIRTY + * mechanism ensures the registers are updated on the + * world switch. + */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) { + /* Enable breakpoints/watchpoints */ + vcpu_sys_reg(vcpu, MDSCR_EL1) |= DBG_MDSCR_MDE; + + vcpu->arch.debug_ptr = &vcpu->arch.external_debug_state; + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; + trap_debug = true; + } } + + BUG_ON(!vcpu->guest_debug && + vcpu->arch.debug_ptr != &vcpu->arch.vcpu_debug_state); + + /* Trap debug register access */ + if (trap_debug) + vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; } void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) { - if (vcpu->guest_debug) + if (vcpu->guest_debug) { restore_guest_debug_regs(vcpu); + + /* + * If we were using HW debug we need to restore the + * debug_ptr to the guest debug state. + */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) + kvm_arm_reset_debug_ptr(vcpu); + + } } diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 48de4f4aaa1a..6f1b249e0587 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -334,6 +334,7 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, #define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE | \ KVM_GUESTDBG_USE_SW_BP | \ + KVM_GUESTDBG_USE_HW | \ KVM_GUESTDBG_SINGLESTEP) /** @@ -354,6 +355,12 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, if (dbg->control & KVM_GUESTDBG_ENABLE) { vcpu->guest_debug = dbg->control; + + /* Hardware assisted Break and Watch points */ + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) { + vcpu->arch.external_debug_state = dbg->arch; + } + } else { /* If not enabled clear all flags */ vcpu->guest_debug = 0; diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index e9de13ed477e..68a0759b1375 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -103,7 +103,11 @@ static int kvm_handle_guest_debug(struct kvm_vcpu *vcpu, struct kvm_run *run) run->debug.arch.hsr = hsr; switch (hsr >> ESR_ELx_EC_SHIFT) { + case ESR_ELx_EC_WATCHPT_LOW: + run->debug.arch.far = vcpu->arch.fault.far_el2; + /* fall through */ case ESR_ELx_EC_SOFTSTP_LOW: + case ESR_ELx_EC_BREAKPT_LOW: case ESR_ELx_EC_BKPT32: case ESR_ELx_EC_BRK64: break; @@ -132,6 +136,8 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug, + [ESR_ELx_EC_WATCHPT_LOW]= kvm_handle_guest_debug, + [ESR_ELx_EC_BREAKPT_LOW]= kvm_handle_guest_debug, [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, }; diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index 0b4326578985..b4af6185713f 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -22,6 +22,7 @@ #include #include #include +#include #include @@ -56,6 +57,12 @@ static bool cpu_has_32bit_el1(void) return !!(pfr0 & 0x20); } +/** + * kvm_arch_dev_ioctl_check_extension + * + * We currently assume that the number of HW registers is uniform + * across all CPUs (see cpuinfo_sanity_check). + */ int kvm_arch_dev_ioctl_check_extension(long ext) { int r; @@ -64,6 +71,15 @@ int kvm_arch_dev_ioctl_check_extension(long ext) case KVM_CAP_ARM_EL1_32BIT: r = cpu_has_32bit_el1(); break; + case KVM_CAP_GUEST_DEBUG_HW_BPS: + r = get_num_brps(); + break; + case KVM_CAP_GUEST_DEBUG_HW_WPS: + r = get_num_wrps(); + break; + case KVM_CAP_SET_GUEST_DEBUG: + r = 1; + break; default: r = 0; } -- cgit From eef8c85a3b81301f912e8802a1dd9f42dd884947 Mon Sep 17 00:00:00 2001 From: Alex Bennée Date: Tue, 7 Jul 2015 17:30:03 +0100 Subject: KVM: arm64: add trace points for guest_debug debug MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This includes trace points for: kvm_arch_setup_guest_debug kvm_arch_clear_guest_debug I've also added some generic register setting trace events and also a trace point to dump the array of hardware registers. Acked-by: Christoffer Dall Signed-off-by: Alex Bennée Signed-off-by: Marc Zyngier --- arch/arm64/kvm/debug.c | 36 +++++++++++++- arch/arm64/kvm/guest.c | 4 ++ arch/arm64/kvm/sys_regs.c | 17 +++++++ arch/arm64/kvm/trace.h | 123 ++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 179 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index 4a99e54d7f3d..47e5f0feaee8 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -18,12 +18,15 @@ */ #include +#include #include #include #include #include +#include "trace.h" + /* These are the bits of MDSCR_EL1 we may manipulate */ #define MDSCR_EL1_DEBUG_MASK (DBG_MDSCR_SS | \ DBG_MDSCR_KDE | \ @@ -44,11 +47,17 @@ static DEFINE_PER_CPU(u32, mdcr_el2); static void save_guest_debug_regs(struct kvm_vcpu *vcpu) { vcpu->arch.guest_debug_preserved.mdscr_el1 = vcpu_sys_reg(vcpu, MDSCR_EL1); + + trace_kvm_arm_set_dreg32("Saved MDSCR_EL1", + vcpu->arch.guest_debug_preserved.mdscr_el1); } static void restore_guest_debug_regs(struct kvm_vcpu *vcpu) { vcpu_sys_reg(vcpu, MDSCR_EL1) = vcpu->arch.guest_debug_preserved.mdscr_el1; + + trace_kvm_arm_set_dreg32("Restored MDSCR_EL1", + vcpu_sys_reg(vcpu, MDSCR_EL1)); } /** @@ -99,6 +108,8 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) { bool trap_debug = !(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY); + trace_kvm_arm_setup_debug(vcpu, vcpu->guest_debug); + vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | MDCR_EL2_TPMCR | @@ -140,6 +151,8 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) vcpu_sys_reg(vcpu, MDSCR_EL1) &= ~DBG_MDSCR_SS; } + trace_kvm_arm_set_dreg32("SPSR_EL2", *vcpu_cpsr(vcpu)); + /* * HW Breakpoints and watchpoints * @@ -156,6 +169,14 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) vcpu->arch.debug_ptr = &vcpu->arch.external_debug_state; vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; trap_debug = true; + + trace_kvm_arm_set_regset("BKPTS", get_num_brps(), + &vcpu->arch.debug_ptr->dbg_bcr[0], + &vcpu->arch.debug_ptr->dbg_bvr[0]); + + trace_kvm_arm_set_regset("WAPTS", get_num_wrps(), + &vcpu->arch.debug_ptr->dbg_wcr[0], + &vcpu->arch.debug_ptr->dbg_wvr[0]); } } @@ -165,10 +186,15 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) /* Trap debug register access */ if (trap_debug) vcpu->arch.mdcr_el2 |= MDCR_EL2_TDA; + + trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2); + trace_kvm_arm_set_dreg32("MDSCR_EL1", vcpu_sys_reg(vcpu, MDSCR_EL1)); } void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) { + trace_kvm_arm_clear_debug(vcpu->guest_debug); + if (vcpu->guest_debug) { restore_guest_debug_regs(vcpu); @@ -176,8 +202,16 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) * If we were using HW debug we need to restore the * debug_ptr to the guest debug state. */ - if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) + if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) { kvm_arm_reset_debug_ptr(vcpu); + trace_kvm_arm_set_regset("BKPTS", get_num_brps(), + &vcpu->arch.debug_ptr->dbg_bcr[0], + &vcpu->arch.debug_ptr->dbg_bvr[0]); + + trace_kvm_arm_set_regset("WAPTS", get_num_wrps(), + &vcpu->arch.debug_ptr->dbg_wcr[0], + &vcpu->arch.debug_ptr->dbg_wvr[0]); + } } } diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 6f1b249e0587..48868d893870 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -32,6 +32,8 @@ #include #include +#include "trace.h" + struct kvm_stats_debugfs_item debugfs_entries[] = { { NULL } }; @@ -350,6 +352,8 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, struct kvm_guest_debug *dbg) { + trace_kvm_set_guest_debug(vcpu, dbg->control); + if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) return -EINVAL; diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 158bae7c52cc..b41607d270ac 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -38,6 +38,8 @@ #include "sys_regs.h" +#include "trace.h" + /* * All of this file is extremly similar to the ARM coproc.c, but the * types are different. My gut feeling is that it should be pretty @@ -208,6 +210,8 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu, *vcpu_reg(vcpu, p->Rt) = vcpu_sys_reg(vcpu, r->reg); } + trace_trap_reg(__func__, r->reg, p->is_write, *vcpu_reg(vcpu, p->Rt)); + return true; } @@ -258,6 +262,8 @@ static inline bool trap_bvr(struct kvm_vcpu *vcpu, else dbg_to_reg(vcpu, p, dbg_reg); + trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg); + return true; } @@ -298,6 +304,8 @@ static inline bool trap_bcr(struct kvm_vcpu *vcpu, else dbg_to_reg(vcpu, p, dbg_reg); + trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg); + return true; } @@ -339,6 +347,9 @@ static inline bool trap_wvr(struct kvm_vcpu *vcpu, else dbg_to_reg(vcpu, p, dbg_reg); + trace_trap_reg(__func__, rd->reg, p->is_write, + vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]); + return true; } @@ -379,6 +390,8 @@ static inline bool trap_wcr(struct kvm_vcpu *vcpu, else dbg_to_reg(vcpu, p, dbg_reg); + trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg); + return true; } @@ -742,6 +755,8 @@ static inline bool trap_xvr(struct kvm_vcpu *vcpu, *vcpu_reg(vcpu, p->Rt) = *dbg_reg >> 32; } + trace_trap_reg(__func__, rd->reg, p->is_write, *dbg_reg); + return true; } @@ -1223,6 +1238,8 @@ int kvm_handle_sys_reg(struct kvm_vcpu *vcpu, struct kvm_run *run) struct sys_reg_params params; unsigned long esr = kvm_vcpu_get_hsr(vcpu); + trace_kvm_handle_sys_reg(esr); + params.is_aarch32 = false; params.is_32bit = false; params.Op0 = (esr >> 20) & 3; diff --git a/arch/arm64/kvm/trace.h b/arch/arm64/kvm/trace.h index 157416e963f2..7fb0008c4fa3 100644 --- a/arch/arm64/kvm/trace.h +++ b/arch/arm64/kvm/trace.h @@ -44,6 +44,129 @@ TRACE_EVENT(kvm_hvc_arm64, __entry->vcpu_pc, __entry->r0, __entry->imm) ); +TRACE_EVENT(kvm_arm_setup_debug, + TP_PROTO(struct kvm_vcpu *vcpu, __u32 guest_debug), + TP_ARGS(vcpu, guest_debug), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(__u32, guest_debug) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->guest_debug = guest_debug; + ), + + TP_printk("vcpu: %p, flags: 0x%08x", __entry->vcpu, __entry->guest_debug) +); + +TRACE_EVENT(kvm_arm_clear_debug, + TP_PROTO(__u32 guest_debug), + TP_ARGS(guest_debug), + + TP_STRUCT__entry( + __field(__u32, guest_debug) + ), + + TP_fast_assign( + __entry->guest_debug = guest_debug; + ), + + TP_printk("flags: 0x%08x", __entry->guest_debug) +); + +TRACE_EVENT(kvm_arm_set_dreg32, + TP_PROTO(const char *name, __u32 value), + TP_ARGS(name, value), + + TP_STRUCT__entry( + __field(const char *, name) + __field(__u32, value) + ), + + TP_fast_assign( + __entry->name = name; + __entry->value = value; + ), + + TP_printk("%s: 0x%08x", __entry->name, __entry->value) +); + +TRACE_EVENT(kvm_arm_set_regset, + TP_PROTO(const char *type, int len, __u64 *control, __u64 *value), + TP_ARGS(type, len, control, value), + TP_STRUCT__entry( + __field(const char *, name) + __field(int, len) + __array(u64, ctrls, 16) + __array(u64, values, 16) + ), + TP_fast_assign( + __entry->name = type; + __entry->len = len; + memcpy(__entry->ctrls, control, len << 3); + memcpy(__entry->values, value, len << 3); + ), + TP_printk("%d %s CTRL:%s VALUE:%s", __entry->len, __entry->name, + __print_array(__entry->ctrls, __entry->len, sizeof(__u64)), + __print_array(__entry->values, __entry->len, sizeof(__u64))) +); + +TRACE_EVENT(trap_reg, + TP_PROTO(const char *fn, int reg, bool is_write, u64 write_value), + TP_ARGS(fn, reg, is_write, write_value), + + TP_STRUCT__entry( + __field(const char *, fn) + __field(int, reg) + __field(bool, is_write) + __field(u64, write_value) + ), + + TP_fast_assign( + __entry->fn = fn; + __entry->reg = reg; + __entry->is_write = is_write; + __entry->write_value = write_value; + ), + + TP_printk("%s %s reg %d (0x%08llx)", __entry->fn, __entry->is_write?"write to":"read from", __entry->reg, __entry->write_value) +); + +TRACE_EVENT(kvm_handle_sys_reg, + TP_PROTO(unsigned long hsr), + TP_ARGS(hsr), + + TP_STRUCT__entry( + __field(unsigned long, hsr) + ), + + TP_fast_assign( + __entry->hsr = hsr; + ), + + TP_printk("HSR 0x%08lx", __entry->hsr) +); + +TRACE_EVENT(kvm_set_guest_debug, + TP_PROTO(struct kvm_vcpu *vcpu, __u32 guest_debug), + TP_ARGS(vcpu, guest_debug), + + TP_STRUCT__entry( + __field(struct kvm_vcpu *, vcpu) + __field(__u32, guest_debug) + ), + + TP_fast_assign( + __entry->vcpu = vcpu; + __entry->guest_debug = guest_debug; + ), + + TP_printk("vcpu: %p, flags: 0x%08x", __entry->vcpu, __entry->guest_debug) +); + + #endif /* _TRACE_ARM64_KVM_H */ #undef TRACE_INCLUDE_PATH -- cgit From bca556ac468ab4744692926b67cb525cdce850c9 Mon Sep 17 00:00:00 2001 From: "Suzuki K. Poulose" Date: Wed, 17 Jun 2015 10:00:46 +0100 Subject: arm64/kvm: Add generic v8 KVM target This patch adds a generic ARM v8 KVM target cpu type for use by the new CPUs which eventualy ends up using the common sys_reg table. For backward compatibility the existing targets have been preserved. Any new target CPU that can be covered by generic v8 sys_reg tables should make use of the new generic target. Signed-off-by: Suzuki K. Poulose Acked-by: Marc Zyngier Signed-off-by: Marc Zyngier --- arch/arm64/include/uapi/asm/kvm.h | 10 ++++++++-- arch/arm64/kvm/guest.c | 3 ++- arch/arm64/kvm/sys_regs_generic_v8.c | 2 ++ 3 files changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index d82f3f316ba4..0cd7b5947dfc 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -53,14 +53,20 @@ struct kvm_regs { struct user_fpsimd_state fp_regs; }; -/* Supported Processor Types */ +/* + * Supported CPU Targets - Adding a new target type is not recommended, + * unless there are some special registers not supported by the + * genericv8 syreg table. + */ #define KVM_ARM_TARGET_AEM_V8 0 #define KVM_ARM_TARGET_FOUNDATION_V8 1 #define KVM_ARM_TARGET_CORTEX_A57 2 #define KVM_ARM_TARGET_XGENE_POTENZA 3 #define KVM_ARM_TARGET_CORTEX_A53 4 +/* Generic ARM v8 target */ +#define KVM_ARM_TARGET_GENERIC_V8 5 -#define KVM_ARM_NUM_TARGETS 5 +#define KVM_ARM_NUM_TARGETS 6 /* KVM_ARM_SET_DEVICE_ADDR ioctl id encoding */ #define KVM_ARM_DEVICE_TYPE_SHIFT 0 diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 48868d893870..d250160d32bc 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -295,7 +295,8 @@ int __attribute_const__ kvm_target_cpu(void) break; }; - return -EINVAL; + /* Return a default generic target */ + return KVM_ARM_TARGET_GENERIC_V8; } int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init) diff --git a/arch/arm64/kvm/sys_regs_generic_v8.c b/arch/arm64/kvm/sys_regs_generic_v8.c index 475fd2929310..1e4576824165 100644 --- a/arch/arm64/kvm/sys_regs_generic_v8.c +++ b/arch/arm64/kvm/sys_regs_generic_v8.c @@ -94,6 +94,8 @@ static int __init sys_reg_genericv8_init(void) &genericv8_target_table); kvm_register_target_sys_reg_table(KVM_ARM_TARGET_XGENE_POTENZA, &genericv8_target_table); + kvm_register_target_sys_reg_table(KVM_ARM_TARGET_GENERIC_V8, + &genericv8_target_table); return 0; } -- cgit From 48f8bd57756573b08520629a2413227fcdf058f5 Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Tue, 28 Jul 2015 10:42:23 +0100 Subject: arm64: KVM: remove remaining reference to vgic_sr_vectors Since commit 8a14849 (arm64: KVM: Switch vgic save/restore to alternative_insn) vgic_sr_vectors is not used anymore, so remove remaining leftovers and kill the structure. Signed-off-by: Vladimir Murzin Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 5 ----- arch/arm64/kernel/asm-offsets.c | 2 -- 2 files changed, 7 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 409217f48456..415938dc45cf 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -246,11 +246,6 @@ static inline void __cpu_init_hyp_mode(phys_addr_t boot_pgd_ptr, hyp_stack_ptr, vector_ptr); } -struct vgic_sr_vectors { - void *save_vgic; - void *restore_vgic; -}; - static inline void kvm_arch_hardware_disable(void) {} static inline void kvm_arch_hardware_unsetup(void) {} static inline void kvm_arch_sync_events(struct kvm *kvm) {} diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index d88630899a24..8d89cf8dae55 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -132,8 +132,6 @@ int main(void) DEFINE(KVM_TIMER_ENABLED, offsetof(struct kvm, arch.timer.enabled)); DEFINE(VCPU_KVM, offsetof(struct kvm_vcpu, kvm)); DEFINE(VCPU_VGIC_CPU, offsetof(struct kvm_vcpu, arch.vgic_cpu)); - DEFINE(VGIC_SAVE_FN, offsetof(struct vgic_sr_vectors, save_vgic)); - DEFINE(VGIC_RESTORE_FN, offsetof(struct vgic_sr_vectors, restore_vgic)); DEFINE(VGIC_V2_CPU_HCR, offsetof(struct vgic_cpu, vgic_v2.vgic_hcr)); DEFINE(VGIC_V2_CPU_VMCR, offsetof(struct vgic_cpu, vgic_v2.vgic_vmcr)); DEFINE(VGIC_V2_CPU_MISR, offsetof(struct vgic_cpu, vgic_v2.vgic_misr)); -- cgit From 9a99d050705318d1cb27979e1c810464347db9db Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 5 Jun 2015 09:33:28 +0100 Subject: arm/arm64: KVM: Fix ordering of timer/GIC on guest entry MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As we now inject the timer interrupt when we're about to enter the guest, it makes a lot more sense to make sure this happens before the vgic code queues the pending interrupts. Otherwise, we get the interrupt on the following exit, which is not great for latency (and leads to all kind of bizarre issues when using with active interrupts at the HW level). Signed-off-by: Marc Zyngier Reviewed-by: Alex Bennée Reviewed-by: Christoffer Dall --- arch/arm/kvm/arm.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 9ce5cf02ed17..1141d21b7e3c 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -523,8 +523,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (vcpu->arch.pause) vcpu_pause(vcpu); - kvm_vgic_flush_hwstate(vcpu); kvm_timer_flush_hwstate(vcpu); + kvm_vgic_flush_hwstate(vcpu); preempt_disable(); local_irq_disable(); @@ -540,8 +540,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) { local_irq_enable(); preempt_enable(); - kvm_timer_sync_hwstate(vcpu); kvm_vgic_sync_hwstate(vcpu); + kvm_timer_sync_hwstate(vcpu); continue; } @@ -587,9 +587,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) trace_kvm_exit(kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); preempt_enable(); - - kvm_timer_sync_hwstate(vcpu); kvm_vgic_sync_hwstate(vcpu); + kvm_timer_sync_hwstate(vcpu); ret = handle_exit(vcpu, run, ret); } -- cgit From abdf58438356c7baf34bdd98084b094ca3a6a23f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 8 Jun 2015 15:00:28 +0100 Subject: arm/arm64: KVM: Move vgic handling to a non-preemptible section MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As we're about to introduce some serious GIC-poking to the vgic code, it is important to make sure that we're going to poke the part of the GIC that belongs to the CPU we're about to run on (otherwise, we'd end up with some unexpected interrupts firing)... Introducing a non-preemptible section in kvm_arch_vcpu_ioctl_run prevents the problem from occuring. Reviewed-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/kvm/arm.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 1141d21b7e3c..f1bf41890fca 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -523,10 +523,20 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (vcpu->arch.pause) vcpu_pause(vcpu); + /* + * Disarming the background timer must be done in a + * preemptible context, as this call may sleep. + */ kvm_timer_flush_hwstate(vcpu); - kvm_vgic_flush_hwstate(vcpu); + /* + * Preparing the interrupts to be injected also + * involves poking the GIC, which must be done in a + * non-preemptible context. + */ preempt_disable(); + kvm_vgic_flush_hwstate(vcpu); + local_irq_disable(); /* @@ -539,8 +549,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) { local_irq_enable(); - preempt_enable(); kvm_vgic_sync_hwstate(vcpu); + preempt_enable(); kvm_timer_sync_hwstate(vcpu); continue; } @@ -585,9 +595,11 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) */ kvm_guest_exit(); trace_kvm_exit(kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu)); - preempt_enable(); kvm_vgic_sync_hwstate(vcpu); + + preempt_enable(); + kvm_timer_sync_hwstate(vcpu); ret = handle_exit(vcpu, run, ret); -- cgit From 32d2d8010cd7080a0f1712f1084b92657858428e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 8 Jun 2015 15:21:32 +0100 Subject: KVM: arm/arm64: vgic: Convert struct vgic_lr to use bitfields MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As we're about to cram more information in the vgic_lr structure (HW interrupt number and additional state information), we switch to a layout similar to the HW's: - use bitfields to save space (we don't need more than 10 bits to represent the irq numbers) - source CPU and HW interrupt can share the same field, as a SGI doesn't have a physical line. Reviewed-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- include/kvm/arm_vgic.h | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 133ea00aa83b..a881e398d3e5 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -95,11 +95,15 @@ enum vgic_type { #define LR_STATE_ACTIVE (1 << 1) #define LR_STATE_MASK (3 << 0) #define LR_EOI_INT (1 << 2) +#define LR_HW (1 << 3) struct vgic_lr { - u16 irq; - u8 source; - u8 state; + unsigned irq:10; + union { + unsigned hwirq:10; + unsigned source:3; + }; + unsigned state:4; }; struct vgic_vmcr { -- cgit From fb182cf84568cc33ab41121bc8cc999f7aacbd47 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 8 Jun 2015 15:37:26 +0100 Subject: KVM: arm/arm64: vgic: Allow HW irq to be encoded in LR Now that struct vgic_lr supports the LR_HW bit and carries a hwirq field, we can encode that information into the list registers. This patch provides implementations for both GICv2 and GICv3. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- include/linux/irqchip/arm-gic-v3.h | 3 +++ include/linux/irqchip/arm-gic.h | 3 ++- virt/kvm/arm/vgic-v2.c | 16 +++++++++++++++- virt/kvm/arm/vgic-v3.c | 21 ++++++++++++++++++--- 4 files changed, 38 insertions(+), 5 deletions(-) diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index ffbc034c8810..cf637d65b589 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -268,9 +268,12 @@ #define ICH_LR_EOI (1UL << 41) #define ICH_LR_GROUP (1UL << 60) +#define ICH_LR_HW (1UL << 61) #define ICH_LR_STATE (3UL << 62) #define ICH_LR_PENDING_BIT (1UL << 62) #define ICH_LR_ACTIVE_BIT (1UL << 63) +#define ICH_LR_PHYS_ID_SHIFT 32 +#define ICH_LR_PHYS_ID_MASK (0x3ffUL << ICH_LR_PHYS_ID_SHIFT) #define ICH_MISR_EOI (1 << 0) #define ICH_MISR_U (1 << 1) diff --git a/include/linux/irqchip/arm-gic.h b/include/linux/irqchip/arm-gic.h index 9de976b4f9a7..ca88dad65260 100644 --- a/include/linux/irqchip/arm-gic.h +++ b/include/linux/irqchip/arm-gic.h @@ -71,11 +71,12 @@ #define GICH_LR_VIRTUALID (0x3ff << 0) #define GICH_LR_PHYSID_CPUID_SHIFT (10) -#define GICH_LR_PHYSID_CPUID (7 << GICH_LR_PHYSID_CPUID_SHIFT) +#define GICH_LR_PHYSID_CPUID (0x3ff << GICH_LR_PHYSID_CPUID_SHIFT) #define GICH_LR_STATE (3 << 28) #define GICH_LR_PENDING_BIT (1 << 28) #define GICH_LR_ACTIVE_BIT (1 << 29) #define GICH_LR_EOI (1 << 19) +#define GICH_LR_HW (1 << 31) #define GICH_VMCR_CTRL_SHIFT 0 #define GICH_VMCR_CTRL_MASK (0x21f << GICH_VMCR_CTRL_SHIFT) diff --git a/virt/kvm/arm/vgic-v2.c b/virt/kvm/arm/vgic-v2.c index f9b9c7c51372..8d7b04db8471 100644 --- a/virt/kvm/arm/vgic-v2.c +++ b/virt/kvm/arm/vgic-v2.c @@ -48,6 +48,10 @@ static struct vgic_lr vgic_v2_get_lr(const struct kvm_vcpu *vcpu, int lr) lr_desc.state |= LR_STATE_ACTIVE; if (val & GICH_LR_EOI) lr_desc.state |= LR_EOI_INT; + if (val & GICH_LR_HW) { + lr_desc.state |= LR_HW; + lr_desc.hwirq = (val & GICH_LR_PHYSID_CPUID) >> GICH_LR_PHYSID_CPUID_SHIFT; + } return lr_desc; } @@ -55,7 +59,9 @@ static struct vgic_lr vgic_v2_get_lr(const struct kvm_vcpu *vcpu, int lr) static void vgic_v2_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc) { - u32 lr_val = (lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT) | lr_desc.irq; + u32 lr_val; + + lr_val = lr_desc.irq; if (lr_desc.state & LR_STATE_PENDING) lr_val |= GICH_LR_PENDING_BIT; @@ -64,6 +70,14 @@ static void vgic_v2_set_lr(struct kvm_vcpu *vcpu, int lr, if (lr_desc.state & LR_EOI_INT) lr_val |= GICH_LR_EOI; + if (lr_desc.state & LR_HW) { + lr_val |= GICH_LR_HW; + lr_val |= (u32)lr_desc.hwirq << GICH_LR_PHYSID_CPUID_SHIFT; + } + + if (lr_desc.irq < VGIC_NR_SGIS) + lr_val |= (lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT); + vcpu->arch.vgic_cpu.vgic_v2.vgic_lr[lr] = lr_val; } diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c index dff06021e748..afbf925b00f4 100644 --- a/virt/kvm/arm/vgic-v3.c +++ b/virt/kvm/arm/vgic-v3.c @@ -67,6 +67,10 @@ static struct vgic_lr vgic_v3_get_lr(const struct kvm_vcpu *vcpu, int lr) lr_desc.state |= LR_STATE_ACTIVE; if (val & ICH_LR_EOI) lr_desc.state |= LR_EOI_INT; + if (val & ICH_LR_HW) { + lr_desc.state |= LR_HW; + lr_desc.hwirq = (val >> ICH_LR_PHYS_ID_SHIFT) & GENMASK(9, 0); + } return lr_desc; } @@ -84,10 +88,17 @@ static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr, * Eventually we want to make this configurable, so we may revisit * this in the future. */ - if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) + switch (vcpu->kvm->arch.vgic.vgic_model) { + case KVM_DEV_TYPE_ARM_VGIC_V3: lr_val |= ICH_LR_GROUP; - else - lr_val |= (u32)lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT; + break; + case KVM_DEV_TYPE_ARM_VGIC_V2: + if (lr_desc.irq < VGIC_NR_SGIS) + lr_val |= (u32)lr_desc.source << GICH_LR_PHYSID_CPUID_SHIFT; + break; + default: + BUG(); + } if (lr_desc.state & LR_STATE_PENDING) lr_val |= ICH_LR_PENDING_BIT; @@ -95,6 +106,10 @@ static void vgic_v3_set_lr(struct kvm_vcpu *vcpu, int lr, lr_val |= ICH_LR_ACTIVE_BIT; if (lr_desc.state & LR_EOI_INT) lr_val |= ICH_LR_EOI; + if (lr_desc.state & LR_HW) { + lr_val |= ICH_LR_HW; + lr_val |= ((u64)lr_desc.hwirq) << ICH_LR_PHYS_ID_SHIFT; + } vcpu->arch.vgic_cpu.vgic_v3.vgic_lr[LR_INDEX(lr)] = lr_val; } -- cgit From 7a67b4b7e04b30345584c1b76a80db628530bf21 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 5 Jun 2015 16:45:29 +0100 Subject: KVM: arm/arm64: vgic: Relax vgic_can_sample_irq for edge IRQs We only set the irq_queued flag for level interrupts, meaning that "!vgic_irq_is_queued(vcpu, irq)" is a good enough predicate for all interrupts. This will allow us to inject edge HW interrupts, for which the state ACTIVE+PENDING is not allowed. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- virt/kvm/arm/vgic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index bc40137a022d..5bd1695845a3 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -375,7 +375,7 @@ void vgic_cpu_irq_clear(struct kvm_vcpu *vcpu, int irq) static bool vgic_can_sample_irq(struct kvm_vcpu *vcpu, int irq) { - return vgic_irq_is_edge(vcpu, irq) || !vgic_irq_is_queued(vcpu, irq); + return !vgic_irq_is_queued(vcpu, irq); } /** -- cgit From 6c3d63c9a26ba56e2ca63a9f68d52f77ae551d91 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 23 Jun 2014 17:37:18 +0100 Subject: KVM: arm/arm64: vgic: Allow dynamic mapping of physical/virtual interrupts In order to be able to feed physical interrupts to a guest, we need to be able to establish the virtual-physical mapping between the two worlds. The mappings are kept in a set of RCU lists, indexed by virtual interrupts. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/kvm/arm.c | 2 + include/kvm/arm_vgic.h | 25 ++++++ virt/kvm/arm/vgic.c | 209 ++++++++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 235 insertions(+), 1 deletion(-) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index f1bf41890fca..ce404a5c3062 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -125,6 +125,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) if (ret) goto out_free_stage2_pgd; + kvm_vgic_early_init(kvm); kvm_timer_init(kvm); /* Mark the initial VMID generation invalid */ @@ -249,6 +250,7 @@ out: void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) { + kvm_vgic_vcpu_early_init(vcpu); } void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index a881e398d3e5..c0e6354bcd06 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -159,6 +159,19 @@ struct vgic_io_device { struct kvm_io_device dev; }; +struct irq_phys_map { + u32 virt_irq; + u32 phys_irq; + u32 irq; + bool active; +}; + +struct irq_phys_map_entry { + struct list_head entry; + struct rcu_head rcu; + struct irq_phys_map map; +}; + struct vgic_dist { spinlock_t lock; bool in_kernel; @@ -256,6 +269,10 @@ struct vgic_dist { struct vgic_vm_ops vm_ops; struct vgic_io_device dist_iodev; struct vgic_io_device *redist_iodevs; + + /* Virtual irq to hwirq mapping */ + spinlock_t irq_phys_map_lock; + struct list_head irq_phys_map_list; }; struct vgic_v2_cpu_if { @@ -307,6 +324,9 @@ struct vgic_cpu { struct vgic_v2_cpu_if vgic_v2; struct vgic_v3_cpu_if vgic_v3; }; + + /* Protected by the distributor's irq_phys_map_lock */ + struct list_head irq_phys_map_list; }; #define LR_EMPTY 0xff @@ -321,8 +341,10 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write); int kvm_vgic_hyp_init(void); int kvm_vgic_map_resources(struct kvm *kvm); int kvm_vgic_get_max_vcpus(void); +void kvm_vgic_early_init(struct kvm *kvm); int kvm_vgic_create(struct kvm *kvm, u32 type); void kvm_vgic_destroy(struct kvm *kvm); +void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu); void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu); void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu); void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu); @@ -331,6 +353,9 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg); int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu); int kvm_vgic_vcpu_active_irq(struct kvm_vcpu *vcpu); +struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, + int virt_irq, int irq); +int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map); #define irqchip_in_kernel(k) (!!((k)->arch.vgic.in_kernel)) #define vgic_initialized(k) (!!((k)->arch.vgic.nr_cpus)) diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 5bd1695845a3..51c990075624 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -74,6 +75,28 @@ * cause the interrupt to become inactive in such a situation. * Conversely, writes to GICD_ICPENDRn do not cause the interrupt to become * inactive as long as the external input line is held high. + * + * + * Initialization rules: there are multiple stages to the vgic + * initialization, both for the distributor and the CPU interfaces. + * + * Distributor: + * + * - kvm_vgic_early_init(): initialization of static data that doesn't + * depend on any sizing information or emulation type. No allocation + * is allowed there. + * + * - vgic_init(): allocation and initialization of the generic data + * structures that depend on sizing information (number of CPUs, + * number of interrupts). Also initializes the vcpu specific data + * structures. Can be executed lazily for GICv2. + * [to be renamed to kvm_vgic_init??] + * + * CPU Interface: + * + * - kvm_vgic_cpu_early_init(): initialization of static data that + * doesn't depend on any sizing information or emulation type. No + * allocation is allowed there. */ #include "vgic.h" @@ -82,6 +105,8 @@ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu); static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu); static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr); static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc); +static struct irq_phys_map *vgic_irq_map_search(struct kvm_vcpu *vcpu, + int virt_irq); static const struct vgic_ops *vgic_ops; static const struct vgic_params *vgic; @@ -1583,6 +1608,164 @@ static irqreturn_t vgic_maintenance_handler(int irq, void *data) return IRQ_HANDLED; } +static struct list_head *vgic_get_irq_phys_map_list(struct kvm_vcpu *vcpu, + int virt_irq) +{ + if (virt_irq < VGIC_NR_PRIVATE_IRQS) + return &vcpu->arch.vgic_cpu.irq_phys_map_list; + else + return &vcpu->kvm->arch.vgic.irq_phys_map_list; +} + +/** + * kvm_vgic_map_phys_irq - map a virtual IRQ to a physical IRQ + * @vcpu: The VCPU pointer + * @virt_irq: The virtual irq number + * @irq: The Linux IRQ number + * + * Establish a mapping between a guest visible irq (@virt_irq) and a + * Linux irq (@irq). On injection, @virt_irq will be associated with + * the physical interrupt represented by @irq. This mapping can be + * established multiple times as long as the parameters are the same. + * + * Returns a valid pointer on success, and an error pointer otherwise + */ +struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, + int virt_irq, int irq) +{ + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + struct list_head *root = vgic_get_irq_phys_map_list(vcpu, virt_irq); + struct irq_phys_map *map; + struct irq_phys_map_entry *entry; + struct irq_desc *desc; + struct irq_data *data; + int phys_irq; + + desc = irq_to_desc(irq); + if (!desc) { + kvm_err("%s: no interrupt descriptor\n", __func__); + return ERR_PTR(-EINVAL); + } + + data = irq_desc_get_irq_data(desc); + while (data->parent_data) + data = data->parent_data; + + phys_irq = data->hwirq; + + /* Create a new mapping */ + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return ERR_PTR(-ENOMEM); + + spin_lock(&dist->irq_phys_map_lock); + + /* Try to match an existing mapping */ + map = vgic_irq_map_search(vcpu, virt_irq); + if (map) { + /* Make sure this mapping matches */ + if (map->phys_irq != phys_irq || + map->irq != irq) + map = ERR_PTR(-EINVAL); + + /* Found an existing, valid mapping */ + goto out; + } + + map = &entry->map; + map->virt_irq = virt_irq; + map->phys_irq = phys_irq; + map->irq = irq; + + list_add_tail_rcu(&entry->entry, root); + +out: + spin_unlock(&dist->irq_phys_map_lock); + /* If we've found a hit in the existing list, free the useless + * entry */ + if (IS_ERR(map) || map != &entry->map) + kfree(entry); + return map; +} + +static struct irq_phys_map *vgic_irq_map_search(struct kvm_vcpu *vcpu, + int virt_irq) +{ + struct list_head *root = vgic_get_irq_phys_map_list(vcpu, virt_irq); + struct irq_phys_map_entry *entry; + struct irq_phys_map *map; + + rcu_read_lock(); + + list_for_each_entry_rcu(entry, root, entry) { + map = &entry->map; + if (map->virt_irq == virt_irq) { + rcu_read_unlock(); + return map; + } + } + + rcu_read_unlock(); + + return NULL; +} + +static void vgic_free_phys_irq_map_rcu(struct rcu_head *rcu) +{ + struct irq_phys_map_entry *entry; + + entry = container_of(rcu, struct irq_phys_map_entry, rcu); + kfree(entry); +} + +/** + * kvm_vgic_unmap_phys_irq - Remove a virtual to physical IRQ mapping + * @vcpu: The VCPU pointer + * @map: The pointer to a mapping obtained through kvm_vgic_map_phys_irq + * + * Remove an existing mapping between virtual and physical interrupts. + */ +int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map) +{ + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + struct irq_phys_map_entry *entry; + struct list_head *root; + + if (!map) + return -EINVAL; + + root = vgic_get_irq_phys_map_list(vcpu, map->virt_irq); + + spin_lock(&dist->irq_phys_map_lock); + + list_for_each_entry(entry, root, entry) { + if (&entry->map == map) { + list_del_rcu(&entry->entry); + call_rcu(&entry->rcu, vgic_free_phys_irq_map_rcu); + break; + } + } + + spin_unlock(&dist->irq_phys_map_lock); + + return 0; +} + +static void vgic_destroy_irq_phys_map(struct kvm *kvm, struct list_head *root) +{ + struct vgic_dist *dist = &kvm->arch.vgic; + struct irq_phys_map_entry *entry; + + spin_lock(&dist->irq_phys_map_lock); + + list_for_each_entry(entry, root, entry) { + list_del_rcu(&entry->entry); + call_rcu(&entry->rcu, vgic_free_phys_irq_map_rcu); + } + + spin_unlock(&dist->irq_phys_map_lock); +} + void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu) { struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; @@ -1591,6 +1774,7 @@ void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu) kfree(vgic_cpu->active_shared); kfree(vgic_cpu->pend_act_shared); kfree(vgic_cpu->vgic_irq_lr_map); + vgic_destroy_irq_phys_map(vcpu->kvm, &vgic_cpu->irq_phys_map_list); vgic_cpu->pending_shared = NULL; vgic_cpu->active_shared = NULL; vgic_cpu->pend_act_shared = NULL; @@ -1627,6 +1811,17 @@ static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs) return 0; } +/** + * kvm_vgic_vcpu_early_init - Earliest possible per-vcpu vgic init stage + * + * No memory allocation should be performed here, only static init. + */ +void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu) +{ + struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; + INIT_LIST_HEAD(&vgic_cpu->irq_phys_map_list); +} + /** * kvm_vgic_get_max_vcpus - Get the maximum number of VCPUs allowed by HW * @@ -1664,6 +1859,7 @@ void kvm_vgic_destroy(struct kvm *kvm) kfree(dist->irq_spi_target); kfree(dist->irq_pending_on_cpu); kfree(dist->irq_active_on_cpu); + vgic_destroy_irq_phys_map(kvm, &dist->irq_phys_map_list); dist->irq_sgi_sources = NULL; dist->irq_spi_cpu = NULL; dist->irq_spi_target = NULL; @@ -1787,6 +1983,18 @@ static int init_vgic_model(struct kvm *kvm, int type) return 0; } +/** + * kvm_vgic_early_init - Earliest possible vgic initialization stage + * + * No memory allocation should be performed here, only static init. + */ +void kvm_vgic_early_init(struct kvm *kvm) +{ + spin_lock_init(&kvm->arch.vgic.lock); + spin_lock_init(&kvm->arch.vgic.irq_phys_map_lock); + INIT_LIST_HEAD(&kvm->arch.vgic.irq_phys_map_list); +} + int kvm_vgic_create(struct kvm *kvm, u32 type) { int i, vcpu_lock_idx = -1, ret; @@ -1832,7 +2040,6 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) if (ret) goto out_unlock; - spin_lock_init(&kvm->arch.vgic.lock); kvm->arch.vgic.in_kernel = true; kvm->arch.vgic.vgic_model = type; kvm->arch.vgic.vctrl_base = vgic->vctrl_base; -- cgit From 08fd6461e8752d2db233c1f237fa5771bcefc63f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 8 Jun 2015 16:06:13 +0100 Subject: KVM: arm/arm64: vgic: Allow HW interrupts to be queued to a guest To allow a HW interrupt to be injected into a guest, we lookup the guest virtual interrupt in the irq_phys_map list, and if we have a match, encode both interrupts in the LR. We also mark the interrupt as "active" at the host distributor level. On guest EOI on the virtual interrupt, the host interrupt will be deactivated. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- virt/kvm/arm/vgic.c | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 86 insertions(+), 3 deletions(-) diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 51c990075624..9d009d2f92f8 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1140,6 +1140,39 @@ static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq, if (!vgic_irq_is_edge(vcpu, irq)) vlr.state |= LR_EOI_INT; + if (vlr.irq >= VGIC_NR_SGIS) { + struct irq_phys_map *map; + map = vgic_irq_map_search(vcpu, irq); + + /* + * If we have a mapping, and the virtual interrupt is + * being injected, then we must set the state to + * active in the physical world. Otherwise the + * physical interrupt will fire and the guest will + * exit before processing the virtual interrupt. + */ + if (map) { + int ret; + + BUG_ON(!map->active); + vlr.hwirq = map->phys_irq; + vlr.state |= LR_HW; + vlr.state &= ~LR_EOI_INT; + + ret = irq_set_irqchip_state(map->irq, + IRQCHIP_STATE_ACTIVE, + true); + WARN_ON(ret); + + /* + * Make sure we're not going to sample this + * again, as a HW-backed interrupt cannot be + * in the PENDING_ACTIVE stage. + */ + vgic_irq_set_queued(vcpu, irq); + } + } + vgic_set_lr(vcpu, lr_nr, vlr); vgic_sync_lr_elrsr(vcpu, lr_nr, vlr); } @@ -1364,6 +1397,39 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) return level_pending; } +/* + * Save the physical active state, and reset it to inactive. + * + * Return 1 if HW interrupt went from active to inactive, and 0 otherwise. + */ +static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr) +{ + struct irq_phys_map *map; + int ret; + + if (!(vlr.state & LR_HW)) + return 0; + + map = vgic_irq_map_search(vcpu, vlr.irq); + BUG_ON(!map || !map->active); + + ret = irq_get_irqchip_state(map->irq, + IRQCHIP_STATE_ACTIVE, + &map->active); + + WARN_ON(ret); + + if (map->active) { + ret = irq_set_irqchip_state(map->irq, + IRQCHIP_STATE_ACTIVE, + false); + WARN_ON(ret); + return 0; + } + + return 1; +} + /* Sync back the VGIC state after a guest run */ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) { @@ -1378,14 +1444,31 @@ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) elrsr = vgic_get_elrsr(vcpu); elrsr_ptr = u64_to_bitmask(&elrsr); - /* Clear mappings for empty LRs */ - for_each_set_bit(lr, elrsr_ptr, vgic->nr_lr) { + /* Deal with HW interrupts, and clear mappings for empty LRs */ + for (lr = 0; lr < vgic->nr_lr; lr++) { struct vgic_lr vlr; - if (!test_and_clear_bit(lr, vgic_cpu->lr_used)) + if (!test_bit(lr, vgic_cpu->lr_used)) continue; vlr = vgic_get_lr(vcpu, lr); + if (vgic_sync_hwirq(vcpu, vlr)) { + /* + * So this is a HW interrupt that the guest + * EOI-ed. Clean the LR state and allow the + * interrupt to be sampled again. + */ + vlr.state = 0; + vlr.hwirq = 0; + vgic_set_lr(vcpu, lr, vlr); + vgic_irq_clear_queued(vcpu, vlr.irq); + set_bit(lr, elrsr_ptr); + } + + if (!test_bit(lr, elrsr_ptr)) + continue; + + clear_bit(lr, vgic_cpu->lr_used); BUG_ON(vlr.irq >= dist->nr_irqs); vgic_cpu->vgic_irq_lr_map[vlr.irq] = LR_EMPTY; -- cgit From 6e84e0e0677281b4e7fc634c7e9d085fbcf41b10 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 8 Jun 2015 16:13:30 +0100 Subject: KVM: arm/arm64: vgic: Add vgic_{get,set}_phys_irq_active In order to control the active state of an interrupt, introduce a pair of accessors allowing the state to be set/queried. This only affects the logical state, and the HW state will only be applied at world-switch time. Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier --- include/kvm/arm_vgic.h | 2 ++ virt/kvm/arm/vgic.c | 24 ++++++++++++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index c0e6354bcd06..e789e4721139 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -356,6 +356,8 @@ int kvm_vgic_vcpu_active_irq(struct kvm_vcpu *vcpu); struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, int virt_irq, int irq); int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map); +bool kvm_vgic_get_phys_irq_active(struct irq_phys_map *map); +void kvm_vgic_set_phys_irq_active(struct irq_phys_map *map, bool active); #define irqchip_in_kernel(k) (!!((k)->arch.vgic.in_kernel)) #define vgic_initialized(k) (!!((k)->arch.vgic.nr_cpus)) diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 9d009d2f92f8..b553a8fa6430 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1801,6 +1801,30 @@ static void vgic_free_phys_irq_map_rcu(struct rcu_head *rcu) kfree(entry); } +/** + * kvm_vgic_get_phys_irq_active - Return the active state of a mapped IRQ + * + * Return the logical active state of a mapped interrupt. This doesn't + * necessarily reflects the current HW state. + */ +bool kvm_vgic_get_phys_irq_active(struct irq_phys_map *map) +{ + BUG_ON(!map); + return map->active; +} + +/** + * kvm_vgic_set_phys_irq_active - Set the active state of a mapped IRQ + * + * Set the logical active state of a mapped interrupt. This doesn't + * immediately affects the HW state. + */ +void kvm_vgic_set_phys_irq_active(struct irq_phys_map *map, bool active) +{ + BUG_ON(!map); + map->active = active; +} + /** * kvm_vgic_unmap_phys_irq - Remove a virtual to physical IRQ mapping * @vcpu: The VCPU pointer -- cgit From 773299a570725d1f253d6046cd6475209b0dcd55 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 24 Jul 2015 11:30:43 +0100 Subject: KVM: arm/arm64: vgic: Prevent userspace injection of a mapped interrupt Virtual interrupts mapped to a HW interrupt should only be triggered from inside the kernel. Otherwise, you could end up confusing the kernel (and the GIC's) state machine. Rearrange the injection path so that kvm_vgic_inject_irq is used for non-mapped interrupts, and kvm_vgic_inject_mapped_irq is used for mapped interrupts. The latter should only be called from inside the kernel (timer, irqfd). Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- include/kvm/arm_vgic.h | 2 + virt/kvm/arm/vgic.c | 103 +++++++++++++++++++++++++++++++++---------------- 2 files changed, 72 insertions(+), 33 deletions(-) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index e789e4721139..d901f1a47be6 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -350,6 +350,8 @@ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu); void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu); int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, bool level); +int kvm_vgic_inject_mapped_irq(struct kvm *kvm, int cpuid, + struct irq_phys_map *map, bool level); void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg); int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu); int kvm_vgic_vcpu_active_irq(struct kvm_vcpu *vcpu); diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index b553a8fa6430..9eb489a2c94c 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1555,7 +1555,8 @@ static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level) } static int vgic_update_irq_pending(struct kvm *kvm, int cpuid, - unsigned int irq_num, bool level) + struct irq_phys_map *map, + unsigned int irq_num, bool level) { struct vgic_dist *dist = &kvm->arch.vgic; struct kvm_vcpu *vcpu; @@ -1563,6 +1564,9 @@ static int vgic_update_irq_pending(struct kvm *kvm, int cpuid, int enabled; bool ret = true, can_inject = true; + if (irq_num >= min(kvm->arch.vgic.nr_irqs, 1020)) + return -EINVAL; + spin_lock(&dist->lock); vcpu = kvm_get_vcpu(kvm, cpuid); @@ -1625,18 +1629,46 @@ static int vgic_update_irq_pending(struct kvm *kvm, int cpuid, out: spin_unlock(&dist->lock); - return ret ? cpuid : -EINVAL; + if (ret) { + /* kick the specified vcpu */ + kvm_vcpu_kick(kvm_get_vcpu(kvm, cpuid)); + } + + return 0; +} + +static int vgic_lazy_init(struct kvm *kvm) +{ + int ret = 0; + + if (unlikely(!vgic_initialized(kvm))) { + /* + * We only provide the automatic initialization of the VGIC + * for the legacy case of a GICv2. Any other type must + * be explicitly initialized once setup with the respective + * KVM device call. + */ + if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2) + return -EBUSY; + + mutex_lock(&kvm->lock); + ret = vgic_init(kvm); + mutex_unlock(&kvm->lock); + } + + return ret; } /** * kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic * @kvm: The VM structure pointer * @cpuid: The CPU for PPIs - * @irq_num: The IRQ number that is assigned to the device + * @irq_num: The IRQ number that is assigned to the device. This IRQ + * must not be mapped to a HW interrupt. * @level: Edge-triggered: true: to trigger the interrupt * false: to ignore the call - * Level-sensitive true: activates an interrupt - * false: deactivates an interrupt + * Level-sensitive true: raise the input signal + * false: lower the input signal * * The GIC is not concerned with devices being active-LOW or active-HIGH for * level-sensitive interrupts. You can think of the level parameter as 1 @@ -1645,39 +1677,44 @@ out: int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, bool level) { - int ret = 0; - int vcpu_id; - - if (unlikely(!vgic_initialized(kvm))) { - /* - * We only provide the automatic initialization of the VGIC - * for the legacy case of a GICv2. Any other type must - * be explicitly initialized once setup with the respective - * KVM device call. - */ - if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2) { - ret = -EBUSY; - goto out; - } - mutex_lock(&kvm->lock); - ret = vgic_init(kvm); - mutex_unlock(&kvm->lock); + struct irq_phys_map *map; + int ret; - if (ret) - goto out; - } + ret = vgic_lazy_init(kvm); + if (ret) + return ret; - if (irq_num >= min(kvm->arch.vgic.nr_irqs, 1020)) + map = vgic_irq_map_search(kvm_get_vcpu(kvm, cpuid), irq_num); + if (map) return -EINVAL; - vcpu_id = vgic_update_irq_pending(kvm, cpuid, irq_num, level); - if (vcpu_id >= 0) { - /* kick the specified vcpu */ - kvm_vcpu_kick(kvm_get_vcpu(kvm, vcpu_id)); - } + return vgic_update_irq_pending(kvm, cpuid, NULL, irq_num, level); +} -out: - return ret; +/** + * kvm_vgic_inject_mapped_irq - Inject a physically mapped IRQ to the vgic + * @kvm: The VM structure pointer + * @cpuid: The CPU for PPIs + * @map: Pointer to a irq_phys_map structure describing the mapping + * @level: Edge-triggered: true: to trigger the interrupt + * false: to ignore the call + * Level-sensitive true: raise the input signal + * false: lower the input signal + * + * The GIC is not concerned with devices being active-LOW or active-HIGH for + * level-sensitive interrupts. You can think of the level parameter as 1 + * being HIGH and 0 being LOW and all devices being active-HIGH. + */ +int kvm_vgic_inject_mapped_irq(struct kvm *kvm, int cpuid, + struct irq_phys_map *map, bool level) +{ + int ret; + + ret = vgic_lazy_init(kvm); + if (ret) + return ret; + + return vgic_update_irq_pending(kvm, cpuid, map, map->virt_irq, level); } static irqreturn_t vgic_maintenance_handler(int irq, void *data) -- cgit From f120cd6533d21075ab103ae6c225b1697853660d Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 23 Jun 2014 13:59:13 +0100 Subject: KVM: arm/arm64: timer: Allow the timer to control the active state In order to remove the crude hack where we sneak the masked bit into the timer's control register, make use of the phys_irq_map API control the active state of the interrupt. This causes some limited changes to allow for potential error propagation. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/kvm/reset.c | 4 +--- arch/arm64/kvm/reset.c | 4 +--- include/kvm/arm_arch_timer.h | 7 +++++-- virt/kvm/arm/arch_timer.c | 29 ++++++++++++++++++++++------- 4 files changed, 29 insertions(+), 15 deletions(-) diff --git a/arch/arm/kvm/reset.c b/arch/arm/kvm/reset.c index f558c073c023..eeb85858d6bb 100644 --- a/arch/arm/kvm/reset.c +++ b/arch/arm/kvm/reset.c @@ -77,7 +77,5 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) kvm_reset_coprocs(vcpu); /* Reset arch_timer context */ - kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); - - return 0; + return kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); } diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index b4af6185713f..91cf5350b328 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -121,7 +121,5 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) kvm_reset_sys_regs(vcpu); /* Reset timer */ - kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); - - return 0; + return kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); } diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h index e5966758c093..e1e4d7c38dda 100644 --- a/include/kvm/arm_arch_timer.h +++ b/include/kvm/arm_arch_timer.h @@ -52,13 +52,16 @@ struct arch_timer_cpu { /* Timer IRQ */ const struct kvm_irq_level *irq; + + /* VGIC mapping */ + struct irq_phys_map *map; }; int kvm_timer_hyp_init(void); void kvm_timer_enable(struct kvm *kvm); void kvm_timer_init(struct kvm *kvm); -void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, - const struct kvm_irq_level *irq); +int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, + const struct kvm_irq_level *irq); void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu); void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu); void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu); diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index 98c95f2fcba4..76e38d231e99 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -64,10 +64,10 @@ static void kvm_timer_inject_irq(struct kvm_vcpu *vcpu) int ret; struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - timer->cntv_ctl |= ARCH_TIMER_CTRL_IT_MASK; - ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id, - timer->irq->irq, - timer->irq->level); + kvm_vgic_set_phys_irq_active(timer->map, true); + ret = kvm_vgic_inject_mapped_irq(vcpu->kvm, vcpu->vcpu_id, + timer->map, + timer->irq->level); WARN_ON(ret); } @@ -117,7 +117,8 @@ bool kvm_timer_should_fire(struct kvm_vcpu *vcpu) cycle_t cval, now; if ((timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) || - !(timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE)) + !(timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE) || + kvm_vgic_get_phys_irq_active(timer->map)) return false; cval = timer->cntv_cval; @@ -184,10 +185,11 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) timer_arm(timer, ns); } -void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, - const struct kvm_irq_level *irq) +int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, + const struct kvm_irq_level *irq) { struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + struct irq_phys_map *map; /* * The vcpu timer irq number cannot be determined in @@ -196,6 +198,17 @@ void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, * vcpu timer irq number when the vcpu is reset. */ timer->irq = irq; + + /* + * Tell the VGIC that the virtual interrupt is tied to a + * physical interrupt. We do that once per VCPU. + */ + map = kvm_vgic_map_phys_irq(vcpu, irq->irq, host_vtimer_irq); + if (WARN_ON(IS_ERR(map))) + return PTR_ERR(map); + + timer->map = map; + return 0; } void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) @@ -335,6 +348,8 @@ void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; timer_disarm(timer); + if (timer->map) + kvm_vgic_unmap_phys_irq(vcpu, timer->map); } void kvm_timer_enable(struct kvm *kvm) -- cgit From 33c76a0b8126946026fa1122cb774553afae0956 Mon Sep 17 00:00:00 2001 From: Mario Smarduch Date: Thu, 16 Jul 2015 22:29:37 +0100 Subject: arm64: KVM: Optimize arm64 skip 30-50% vfp/simd save/restore on exits This patch only saves and restores FP/SIMD registers on Guest access. To do this cptr_el2 FP/SIMD trap is set on Guest entry and later checked on exit. lmbench, hackbench show significant improvements, for 30-50% exits FP/SIMD context is not saved/restored [chazy/maz: fixed save/restore logic for 32bit guests] Signed-off-by: Mario Smarduch Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_arm.h | 5 ++- arch/arm64/kvm/hyp.S | 73 +++++++++++++++++++++++++++++++++++----- 2 files changed, 68 insertions(+), 10 deletions(-) diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index ac6fafb95fe7..7605e095217f 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -171,10 +171,13 @@ #define HSTR_EL2_TTEE (1 << 16) #define HSTR_EL2_T(x) (1 << x) +/* Hyp Coproccessor Trap Register Shifts */ +#define CPTR_EL2_TFP_SHIFT 10 + /* Hyp Coprocessor Trap Register */ #define CPTR_EL2_TCPAC (1 << 31) #define CPTR_EL2_TTA (1 << 20) -#define CPTR_EL2_TFP (1 << 10) +#define CPTR_EL2_TFP (1 << CPTR_EL2_TFP_SHIFT) /* Hyp Debug Configuration Register bits */ #define MDCR_EL2_TDRA (1 << 11) diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index d93c0a23630e..8188f6ae8fc4 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -385,6 +385,14 @@ tbz \tmp, #KVM_ARM64_DEBUG_DIRTY_SHIFT, \target .endm +/* + * Branch to target if CPTR_EL2.TFP bit is set (VFP/SIMD trapping enabled) + */ +.macro skip_fpsimd_state tmp, target + mrs \tmp, cptr_el2 + tbnz \tmp, #CPTR_EL2_TFP_SHIFT, \target +.endm + .macro compute_debug_state target // Compute debug state: If any of KDE, MDE or KVM_ARM64_DEBUG_DIRTY // is set, we do a full save/restore cycle and disable trapping. @@ -423,10 +431,12 @@ add x3, x2, #CPU_SYSREG_OFFSET(DACR32_EL2) mrs x4, dacr32_el2 mrs x5, ifsr32_el2 - mrs x6, fpexc32_el2 stp x4, x5, [x3] - str x6, [x3, #16] + skip_fpsimd_state x8, 3f + mrs x6, fpexc32_el2 + str x6, [x3, #16] +3: skip_debug_state x8, 2f mrs x7, dbgvcr32_el2 str x7, [x3, #24] @@ -453,10 +463,8 @@ add x3, x2, #CPU_SYSREG_OFFSET(DACR32_EL2) ldp x4, x5, [x3] - ldr x6, [x3, #16] msr dacr32_el2, x4 msr ifsr32_el2, x5 - msr fpexc32_el2, x6 skip_debug_state x8, 2f ldr x7, [x3, #24] @@ -473,8 +481,22 @@ .macro activate_traps ldr x2, [x0, #VCPU_HCR_EL2] + + /* + * We are about to set CPTR_EL2.TFP to trap all floating point + * register accesses to EL2, however, the ARM ARM clearly states that + * traps are only taken to EL2 if the operation would not otherwise + * trap to EL1. Therefore, always make sure that for 32-bit guests, + * we set FPEXC.EN to prevent traps to EL1, when setting the TFP bit. + */ + tbnz x2, #HCR_RW_SHIFT, 99f // open code skip_32bit_state + mov x3, #(1 << 30) + msr fpexc32_el2, x3 + isb +99: msr hcr_el2, x2 mov x2, #CPTR_EL2_TTA + orr x2, x2, #CPTR_EL2_TFP msr cptr_el2, x2 mov x2, #(1 << 15) // Trap CP15 Cr=15 @@ -488,7 +510,6 @@ .macro deactivate_traps mov x2, #HCR_RW msr hcr_el2, x2 - msr cptr_el2, xzr msr hstr_el2, xzr mrs x2, mdcr_el2 @@ -653,12 +674,41 @@ __restore_debug: ret __save_fpsimd: + skip_fpsimd_state x3, 1f save_fpsimd - ret +1: ret __restore_fpsimd: + skip_fpsimd_state x3, 1f restore_fpsimd - ret +1: ret + +switch_to_guest_fpsimd: + push x4, lr + + mrs x2, cptr_el2 + bic x2, x2, #CPTR_EL2_TFP + msr cptr_el2, x2 + isb + + mrs x0, tpidr_el2 + + ldr x2, [x0, #VCPU_HOST_CONTEXT] + kern_hyp_va x2 + bl __save_fpsimd + + add x2, x0, #VCPU_CONTEXT + bl __restore_fpsimd + + skip_32bit_state x3, 1f + ldr x4, [x2, #CPU_SYSREG_OFFSET(FPEXC32_EL2)] + msr fpexc32_el2, x4 +1: + pop x4, lr + pop x2, x3 + pop x0, x1 + + eret /* * u64 __kvm_vcpu_run(struct kvm_vcpu *vcpu); @@ -680,7 +730,6 @@ ENTRY(__kvm_vcpu_run) kern_hyp_va x2 save_host_regs - bl __save_fpsimd bl __save_sysregs compute_debug_state 1f @@ -697,7 +746,6 @@ ENTRY(__kvm_vcpu_run) add x2, x0, #VCPU_CONTEXT bl __restore_sysregs - bl __restore_fpsimd skip_debug_state x3, 1f ldr x3, [x0, #VCPU_DEBUG_PTR] @@ -740,6 +788,8 @@ __kvm_vcpu_return: bl __restore_sysregs bl __restore_fpsimd + /* Clear FPSIMD and Trace trapping */ + msr cptr_el2, xzr skip_debug_state x3, 1f // Clear the dirty flag for the next run, as all the state has @@ -949,6 +999,11 @@ el1_trap: * x1: ESR * x2: ESR_EC */ + + /* Guest accessed VFP/SIMD registers, save host, restore Guest */ + cmp x2, #ESR_ELx_EC_FP_ASIMD + b.eq switch_to_guest_fpsimd + cmp x2, #ESR_ELx_EC_DABT_LOW mov x0, #ESR_ELx_EC_IABT_LOW ccmp x2, x0, #4, ne -- cgit From 054167b3d55127feb64978eddf3f9f3a84fe493b Mon Sep 17 00:00:00 2001 From: Mario Smarduch Date: Thu, 16 Jul 2015 22:29:38 +0100 Subject: arm: KVM: keep arm vfp/simd exit handling consistent with arm64 After enhancing arm64 FP/SIMD exit handling, ARMv7 VFP exit branch is moved to guest trap handling. This allows us to keep exit handling flow between both architectures consistent. Signed-off-by: Mario Smarduch Signed-off-by: Marc Zyngier --- arch/arm/kvm/interrupts.S | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S index 568494dbbbb5..900ef6dd8f72 100644 --- a/arch/arm/kvm/interrupts.S +++ b/arch/arm/kvm/interrupts.S @@ -361,10 +361,6 @@ hyp_hvc: @ Check syndrome register mrc p15, 4, r1, c5, c2, 0 @ HSR lsr r0, r1, #HSR_EC_SHIFT -#ifdef CONFIG_VFPv3 - cmp r0, #HSR_EC_CP_0_13 - beq switch_to_guest_vfp -#endif cmp r0, #HSR_EC_HVC bne guest_trap @ Not HVC instr. @@ -378,7 +374,10 @@ hyp_hvc: cmp r2, #0 bne guest_trap @ Guest called HVC -host_switch_to_hyp: + /* + * Getting here means host called HVC, we shift parameters and branch + * to Hyp function. + */ pop {r0, r1, r2} /* Check for __hyp_get_vectors */ @@ -409,6 +408,10 @@ guest_trap: @ Check if we need the fault information lsr r1, r1, #HSR_EC_SHIFT +#ifdef CONFIG_VFPv3 + cmp r1, #HSR_EC_CP_0_13 + beq switch_to_guest_vfp +#endif cmp r1, #HSR_EC_IABT mrceq p15, 4, r2, c6, c0, 2 @ HIFAR beq 2f @@ -477,7 +480,6 @@ guest_trap: */ #ifdef CONFIG_VFPv3 switch_to_guest_vfp: - load_vcpu @ Load VCPU pointer to r0 push {r3-r7} @ NEON/VFP used. Turn on VFP access. -- cgit